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On the Lighter Side => New Theories => Topic started by: Jaaanosik on 01/08/2020 21:00:02

Title: Is Special Relativity reciprocal?
Post by: Jaaanosik on 01/08/2020 21:00:02
... as per the parent thread:

Hi all,
Is the Lorentz Contraction real or not real.
What a beautiful 'can of warms' we got open here. :)
We all want to find out the truth.
If we come close to finding out the truth we will also find the answer to the question of this thread: Is angular momentum frame dependent?

I suggest we all put aside our convictions what is the correct answer and we develop an argument together; we find the answer together.
There are good points on both sides, to show that the LC is not real and also to show that the LC is real.
First, let us discuss how we can show the LC is not real.
I'll make a statement and I suggest we get an agreement if the statement can lead towards the answer.
If we say yes, then we will analyze and prove the statement.

If the Special Relativity is reciprocal then the Lorentz Contraction is not real.

Please, let us discuss the statement above. Do we agree it is a true statement?
Jano
If the Special Relativity is reciprocal then the Lorentz Contraction is not real.

Please, let us discuss the statement above. Do we agree it is a true statement?
Jano

What do you mean by special relativity being "reciprocal"?



Two inertial observers see each other clocks going slower.
Two inertial observers see each other Lorentz Contracted.
Whatever the first inertial observer can say about the second one then the second observer can say the same things about the first one.
There is no preferred reference frame.
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 01/08/2020 21:03:13
Both observers are correct and length contraction is real.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 01/08/2020 21:18:09
Both observers are correct and length contraction is real.

They cannot be both real because of the Twin paradox.
If two twins meet again and there is a delta of their clocks then this proves the LC is real and this proves the SR is not reciprocal.

If we can show the Twin paradox stays as a paradox then the SR is reciprocal and LC is not real.
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 01/08/2020 21:51:42
The twin paradox is not actually a paradox. Length contraction is real in both frames.
Title: Re: Is Special Relativity reciprocal?
Post by: Bored chemist on 01/08/2020 22:23:01
They cannot be both real because of the Twin paradox.
If you were stood next to either of them you would agree that what they see is real.

The twin paradox is not  symmetrical. Only one twin experiences the acceleration of the ship. So it's not really a paradox.
Title: Re: Is Special Relativity reciprocal?
Post by: CPT ArkAngel on 02/08/2020 02:59:45
They must be in the same frame at the start to synchronized a common proper clock to validate the reality of time dilation. The time dilation corresponds to the difference of the total length of the two different paths from the point of view of the meeting point. This time dilation is measured so it is absolutely real. When the paths are symmetrical, meaning their acceleration are equal and opposite at all time from the point of view of the meeting point, there is an apparent time dilation for sure but there is no way to say it is real or not because when they meet they have the same age, but within Special Relativity it must be real. Special relativity is consistent but you must know who is accelerating. One feels the acceleration, the other not.
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 02/08/2020 04:51:17
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 02/08/2020 05:09:00
There are good points on both sides, to show that the LC is not real and also to show that the LC is real.
First, let us discuss how we can show the LC is not real.
I'll make a statement and I suggest we get an agreement if the statement can lead towards the answer.
If we say yes, then we will analyze and prove the statement.

If the Special Relativity is reciprocal then the Lorentz Contraction is not real.
1) You'd have to show that SR is reciprocal in all cases, not just one. It isn't.
2) I don't agree with your statement at all. SR could be completely reciprocal and LC could still be real.



Quote
What do you mean by special relativity being "reciprocal"?
Two inertial observers see each other clocks going slower.
Two inertial observers see each other Lorentz Contracted.
This is one example, which doesn't define what you mean by reciprocal. It helps I suppose.

Quote
Whatever the first inertial observer can say about the second one then the second observer can say the same things about the first one.
That's clearly not always true.

Quote
There is no preferred reference frame.
It can be shown that if there is a preferred reference frame, there is no local way to detect it. This fact has nothing to do with LC being real or SR being reciprocal.

They cannot be both real because of the Twin paradox.
The twins scenario is not symmetric. If I smash my finger and have a broken bone and you don't, it doesn't prove that SR isn't reciprocal. It isn't, but not because of the finger.

The rotating examples is where all observers agree on real length contraction.  I can have two identical circular wedding rings, and if I spin one fast enough, length contraction will let me pass the spinning one through the other. All observers will agree that I did that, so LC is real.  Simple as that.
Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 02/08/2020 14:24:43
If the Special Relativity is reciprocal then the Lorentz Contraction is not real.

Please, let us discuss the statement above. Do we agree it is a true statement?
No, we do not agree. There is no reason to suggest it is.

Two inertial observers see each other clocks going slower.
Two inertial observers see each other Lorentz Contracted.
Whatever the first inertial observer can say about the second one then the second
observer can say the same things about the first one.
All these statements refer to inertial observers and inertial reference frames. If you introduce accelerating frames you will find that when the observers come together in a common, local frame they will not agree on the amount of time each has experienced, nor will they agree on the amount of distance the traveller has covered - due to length contraction.

There is no preferred reference frame.
All inertial frames are preferred frames in SR, accelerating frames are not.

Time dilation/length contraction is real and relativistic effects have been verified by experiment eg in particle accelerators. If Einstein had not discovered relativity its existence would have become obvious with the advent of particle physics.
 
Title: Re: Is Special Relativity reciprocal?
Post by: yor_on on 02/08/2020 15:34:34
Myself it's a question of logic versus magic. I expect this universes to consist of a logic.. It may not fit what we once observed, times gone, but it needs logic to make me happy. It's a very centric view but it's also the one mathematics expect to be true.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 02/08/2020 18:19:29
Here is one figure, I hope this helps with the definition of what the reciprocal means.

(https://i.imgur.com/L6PbNmo.png)

What do you see?
It appears to me that trains 90 degree beam propagates at c/2 for the platform observer.
... and platform 90 degree beam propagates at c/2 for the train observer.

This is the definition of reciprocal in my view.
Do we have an agreement?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 02/08/2020 23:25:57
This is the definition of reciprocal in my view.
Do we have an agreement?
No, we do not. Your diagram doesnít make sense, nor does it define reciprocal.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 03/08/2020 01:00:06
No, it is not reciprocal. We can see this in a case where one clock travels round and round in circles with another clock in the centre of the circle. Let's say that these clocks are in spaceships with the circling one always moving at 0.866c relative to the central one. If they are transmitting video to each other, the crew of the central ship will see the people in the other ship living in slow motion, and their clock will confirm it, ticking half as often as the central ship's clock. However, in the circling ship, when they watch the video coming from the central ship, they see the people in it moving about very fast, and they see that the clock there is ticking at twice the rate of their own clock. So it is not symmetrical.

How do defenders of STR deal with this? They assert that STR can't handle it because of the involvement of acceleration and that you have to switch to GTR, but that's a bogus argument. You can eliminate the accelerations by having lots of other clocks moving at 0.866c along tangents to the circle make timings of the almost exactly the same course by acting as a relay team, passing a virtual baton to each other when they pass each other. Here's an animation of it magicschoolbook.com/science/STR-disproof-5.html (http://magicschoolbook.com/science/STR-disproof-5.html) to help you visualise it correctly. These clocks moving along tangents to the curve tick at the same rate as the circling clock while they accompany it during their leg of the relay. No matter which frame of reference you use to analyse this, you determine that the clocks moving along tangents are ticking on average at half the rate of the central clock. That is not symmetrical. There are certainly some clocks in there that are not accelerating at any point which are ticking slower than the central clock, even though there is no possible mechanism in STR to allow them to do so.
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 03/08/2020 03:04:28
passing a virtual baton to each other when they pass each other.

The act of "passing the baton" will require acceleration, because the direction that the mass-energy aboard the ship is moving will change every time a signal (which must be composed of that same mass-energy) is passed from one ship to the other.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 03/08/2020 03:30:46
This is the definition of reciprocal in my view.
Do we have an agreement?
No, we do not. Your diagram doesnít make sense, nor does it define reciprocal.


What is wrong with the diagram?
What does not make sense?
Please, be more specific.
The diagram is kind of self explanatory, isn't it?
Jano

Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 03/08/2020 03:33:25
No, it is not reciprocal. We can see this in a case where one clock travels round and round in circles with another clock in the centre of the circle. Let's say that these clocks are in spaceships with the circling one always moving at 0.866c relative to the central one. If they are transmitting video to each other, the crew of the central ship will see the people in the other ship living in slow motion, and their clock will confirm it, ticking half as often as the central ship's clock. However, in the circling ship, when they watch the video coming from the central ship, they see the people in it moving about very fast, and they see that the clock there is ticking at twice the rate of their own clock. So it is not symmetrical.

How do defenders of STR deal with this? They assert that STR can't handle it because of the involvement of acceleration and that you have to switch to GTR, but that's a bogus argument. You can eliminate the accelerations by having lots of other clocks moving at 0.866c along tangents to the circle make timings of the almost exactly the same course by acting as a relay team, passing a virtual baton to each other when they pass each other. Here's an animation of it magicschoolbook.com/science/STR-disproof-5.html (http://magicschoolbook.com/science/STR-disproof-5.html) to help you visualise it correctly. These clocks moving along tangents to the curve tick at the same rate as the circling clock while they accompany it during their leg of the relay. No matter which frame of reference you use to analyse this, you determine that the clocks moving along tangents are ticking on average at half the rate of the central clock. That is not symmetrical. There are certainly some clocks in there that are not accelerating at any point which are ticking slower than the central clock, even though there is no possible mechanism in STR to allow them to do so.

What are you talking about?
There is no circle in the diagram. Please, stay true what is presented on the diagram,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 03/08/2020 03:35:37
passing a virtual baton to each other when they pass each other.

The act of "passing the baton" will require acceleration, because the direction that the mass-energy aboard the ship is moving will change every time a signal (which must be composed of that same mass-energy) is passed from one ship to the other.
Whatever David says is not relevant, there is no acceleration involved in the Figure presented,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 03/08/2020 05:01:33
David was commenting that there exist scenarios where relativity is not reciprocal. I agree with him on that point. He incorrectly asserts that SR cannot handle acceleration, but is gravity that SR cannot handle.

You simply presented one example that was reciprocal according to your definition, but it isn't always the case as evidenced by David's counter-example and several other counter-examples in the other thread.

Length contraction being real or not does not hinge on this reciprocal property, so I don't know what you think has been illustrated by it all. I thought M-L had a better definition: It is real if there is a real consequence that all observers can agree on, such as one twin being older than another.
Title: Re: Is Special Relativity reciprocal?
Post by: arjeet45o on 03/08/2020 07:08:38
The twin paradox is not actually a paradox
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 03/08/2020 18:22:19
David was commenting that there exist scenarios where relativity is not reciprocal. I agree with him on that point. He incorrectly asserts that SR cannot handle acceleration, but is gravity that SR cannot handle.

You simply presented one example that was reciprocal according to your definition, but it isn't always the case as evidenced by David's counter-example and several other counter-examples in the other thread.

Length contraction being real or not does not hinge on this reciprocal property, so I don't know what you think has been illustrated by it all. I thought M-L had a better definition: It is real if there is a real consequence that all observers can agree on, such as one twin being older than another.

(https://i.imgur.com/L6PbNmo.png)

What is the distance the train observer moved in the platform frame in 2s of the platform time? 1.732cs
What is the distance the platform observer moved in the train frame in 2s' of the train time? 1.732cs'
How is this possible to be true for both observers if there is a length contraction?
We have to go to relativity of simultaneity, clock desynchronization, ... to explain it.
The problem is that whatever explanation is done from the first frame then it can be applied to the second frame in the reciprocal way.
This is the paradox, it does not go away,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 03/08/2020 18:27:56
The twin paradox is not actually a paradox

Twin Paradox stays as a paradox in SR.
The Triplet Paradox is even better:

(https://i.imgur.com/QbyqCQl.png)

Two triplet observers do not agree on the proper time of the third triplet.
When they meet again they just do not have a solution.
What values would be on their clocks?
What time there would be on ct'' clock?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 03/08/2020 21:04:34
passing a virtual baton to each other when they pass each other.

The act of "passing the baton" will require acceleration, because the direction that the mass-energy aboard the ship is moving will change every time a signal (which must be composed of that same mass-energy) is passed from one ship to the other.

It's a virtual baton - there is no actual baton passed. The relay race is just a different way of timing the trip. Instead of relying on the red clock's timing of the complete circuit, we have the blue and green clocks take turns to time straight-line approximations of the red clock's path, and those timers are not affected by accelerations as they never accelerate. Their collective relay path is sufficiently alike to the red clock's circular path that they show the validity of the red clock's timing and reveal that the continual acceleration acting on the red clock does not make it tick differently from any non-accelerating clock that approximately accompanies it for a while. For any frame of reference you care to choose, a set of blue and green clocks can approximate the circular or elliptical path of the red clock to a high degree of precision, and bearing in mind that the red clock ticks at half the rate of the white clock at the centre, you'd need one hell of a big difference between the ticking rate of the red clock and an accompanying blue/green clock to destroy the evidence provided by this thought experiment.

We can find frames of reference where some of the green/blue clocks can be said to be ticking faster than the white clock, but in each case, that goes along with there being other green/blue clocks in the system which are ticking much slower than the white clock: the average for the blue and green clocks used as totted up for their legs of the relay always lead to a timing that shows an average tick rate of half that of the white clock. There are some clocks in the system which definitively tick at a lower rate than the white clock and which never accelerate, and it doesn't matter which ones they are: we know that they exist.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 03/08/2020 21:10:57
What are you talking about?
There is no circle in the diagram. Please, stay true what is presented on the diagram,
Jano

The red dot (representing a clock) travels in circles around the white clock. (The blue and green dots follow straight lines at all times.) Some people who are red-green colourblind have difficulty seeing red against a black background, so I may need to change it to a different colour if that's the issue here.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 03/08/2020 21:28:20
The twin paradox is not actually a paradox

It isn't a paradox as it has a resolution in LET, but it remains a paradox in STR. Just as you can remove the acceleration issue from the circling case, you can do this with the twins paradox, so let's do that now. If we give the stay-at-home twin clock A, then the other twin can travel with clock B away and back at 0.866c. On return, when they compare their timings for the separation, clock A ticked twice as many times as clock B, so clock B was clearly ticking slow, but people like to attribute that to the accelerations. We can eliminate the role for acceleration though just by introducing two additional clocks. Clock C travels alongside clock B on the outward leg, and clock D travels alongside clock D on the return leg. Neither of these new clocks accelerates at any point. Clock C makes a timing from when it passes clock A until it passes clock D. Clock D makes a timing from when it passes clock C to when it passes clock A. Timing B = timings C+D, confirming that the only role for the accelerations of clock B was to change its absolute speed of motion through space. We get the result timing A = 2(C+D).

In all cases with the twins paradox, you get A > C+D. Without a space fabric and absolute frame, clocks A, C and D would all have to be ticking at the same rate as each other, but that would give us the result A = C+D, which is a result that the universe never provides. STR demands that A ticks faster than C while C ticks faster than A. It also demands that A ticks faster than D while D ticks faster than A, and that C ticks faster than D while D ticks faster than C. Those are all paradoxical. But what the twins paradox shows us is that A always ticks faster than C or D (if not than both of them), and that's an asymmetrical requirement. The only symmetry involved in it is with our inability to pin down whether A is ticking faster than C or D if it isn't ticking faster than both of them, but A > C+D demands that A is ticking faster than the average of C and D. There has to be a relationship between A and C or A and D in which A is ticking at a faster rate than the other clock while that other clock cannot also be ticking faster than A. The symmetry breaks.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 03/08/2020 22:40:56
(https://i.imgur.com/4M8UaOI.png)

From this book:

(https://i.imgur.com/Vurc6NV.png)

Why is the author saying that time on the Earth is flowing more slowly?
Because it is based on the SR, the time dilation is reciprocal.
Please, have a look here:

(https://i.imgur.com/6MCSVif.png)

The mysterious jump cannot happen.
The event P or the event C in the other diagram are when the travelling twin stops at the return point.
This is the spot where both twins are in the same reference frame. There is nothing weird happening.
The question is what is the time on the clocks at the turning point when they are in the same frame and the simultaneity line is the straight horizontal line?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 03/08/2020 23:52:41
It isn't a paradox as it has a resolution in LET, but it remains a paradox in STR.

I thought Lorentz ether theory and special relativity made identical physical predictions, the only difference being some of the underlying mechanics where LET invokes an ether and SR does not.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 04/08/2020 13:25:31
The twin paradox is not actually a paradox

It isn't a paradox as it has a resolution in LET, but it remains a paradox in STR. Just as you can remove the acceleration issue from the circling case, you can do this with the twins paradox, so let's do that now. If we give the stay-at-home twin clock A, then the other twin can travel with clock B away and back at 0.866c. On return, when they compare their timings for the separation, clock A ticked twice as many times as clock B, so clock B was clearly ticking slow, but people like to attribute that to the accelerations. We can eliminate the role for acceleration though just by introducing two additional clocks. Clock C travels alongside clock B on the outward leg, and clock D travels alongside clock D on the return leg. Neither of these new clocks accelerates at any point. Clock C makes a timing from when it passes clock A until it passes clock D. Clock D makes a timing from when it passes clock C to when it passes clock A. Timing B = timings C+D, confirming that the only role for the accelerations of clock B was to change its absolute speed of motion through space. We get the result timing A = 2(C+D).

In all cases with the twins paradox, you get A > C+D. Without a space fabric and absolute frame, clocks A, C and D would all have to be ticking at the same rate as each other, but that would give us the result A = C+D, which is a result that the universe never provides. STR demands that A ticks faster than C while C ticks faster than A. It also demands that A ticks faster than D while D ticks faster than A, and that C ticks faster than D while D ticks faster than C. Those are all paradoxical. But what the twins paradox shows us is that A always ticks faster than C or D (if not than both of them), and that's an asymmetrical requirement. The only symmetry involved in it is with our inability to pin down whether A is ticking faster than C or D if it isn't ticking faster than both of them, but A > C+D demands that A is ticking faster than the average of C and D. There has to be a relationship between A and C or A and D in which A is ticking at a faster rate than the other clock while that other clock cannot also be ticking faster than A. The symmetry breaks.
The Triplet paradox cannot be resolved with the logic posted above, just check the times here:

(https://i.imgur.com/QbyqCQl.png)

The times will not add up. Why is that?
The acceleration is not an issue, agreed:

(https://i.imgur.com/6MCSVif.png)

Because it can be replaced with the average relative motion as per the figure above,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 04/08/2020 15:27:03

(https://i.imgur.com/C4TkonR.png)

Kryptid,
Question, how is it possible that when the travelling twin is in 'the same reference' frame, has almost 0 relative speed there are the biggest proper time deltas between the reference frames?
Please, see the blue lines.
Do you agree that this does not make sense?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 04/08/2020 23:23:51
It isn't a paradox as it has a resolution in LET, but it remains a paradox in STR.

I thought Lorentz ether theory and special relativity made identical physical predictions, the only difference being some of the underlying mechanics where LET invokes an ether and SR does not.

No. LET makes conditional predictions (meaning that they're all predicated by "if this is the absolute frame") while STR makes absolute ones (in which the absolute frame is denied and all the predictions are considered absolutely correct even when they contradict each other). The latter retains a paradox in its toleration of contradiction.

For example, suppose clock A (the stay-at-home twin's clock) sounds an alarm half way between twin B's departure and return. When twin B is at the turning point half way through, we can have him do a little jiggle where he accelerates to turn round and accelerates to 0.866c towards home, then accelerates to turn back and go outwards again for a moment at 0.866c away from home, then accelerates to turn back again for the long return towards home at 0.866c. Look at the predictions that he makes between those accelerations when moving at constant speed. Just before the first turn round, his calculations using STR where he counts himself as stationary tell him that the alarm has not sounded yet at clock A. After the first of the three turn-arounds, his new calculation using the new frame that he's stationary in tells him that the alarm has sounded at clock A. After the second turn-around, his new calculation tells him that the alarm has not sounded yet at clock A, and after the third turn-around, his new calculation tells him that the alarm has sounded at clock A. These predictions in STR are all supposed to be equally valid, but mathematics tells us that they cannot all be true because the middle two contradict each other, and if they are not equally true, they are not equally valid. In LET, they do not contradict because the predictions are conditional and the conditions are not always met.
Title: Re: Is Special Relativity reciprocal?
Post by: alancalverd on 04/08/2020 23:57:08


The red dot (representing a clock) travels in circles around the white clock.

And there's your problem. Circular motion requires continuous acceleration towards the center of the circle, so there is no symmetry between an orbiting twin and a stationary one.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 05/08/2020 00:38:54
I thought Lorentz ether theory and special relativity made identical physical predictions, the only difference being some of the underlying mechanics where LET invokes an ether and SR does not.
The two theories do make identical predictions. Dave has a long history of creating straw man arguments against SR, such as the statement below:

LET makes conditional predictions (meaning that they're all predicated by "if this is the absolute frame") while STR makes absolute ones
On that note, it seems that if LET asserts that, then lacking a frame that satisfies the requirements of the interpretation, the interpretation must be false. Oh sure, it works under Minkowski flat spacetime, but the universe is not modeled by that kind of spacetime. No known coordinate system orders all events in all of spacetime, so any theory that asserts such an ordering must be false.
Notably, an inertial coordinate system behaves empirically different than the universe we observe.  Secondly, while there are some coordinate systems that can objectively order all events inside and outside an evaporating black hole, but none do so for more than one black hole.

Suppose I drop a clock into a large black hole. It reads midnight when it passes the event horizon.  One event is that clock when it reads one second past midnight.  Another event is a point in normal space near where that black hole finished evaporating an hour ago.  Which event occurs first and where along the worldline of the later clock is an event simultaneous with the earlier event?  Assume any method you like for the objective frame, but one must be chosen. The lack of a candidate coordinate system means there cannot be an objective one.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 05/08/2020 04:11:13


The red dot (representing a clock) travels in circles around the white clock.

And there's your problem. Circular motion requires continuous acceleration towards the center of the circle, so there is no symmetry between an orbiting twin and a stationary one.

The whole point of this example is that the circular motion is eliminated by the other clocks forming a relay race round the same circuit with them all moving along straight paths and confirming that the acceleration is irrelevant: it shows the case with acceleration to map with high precision to the case without acceleration, and if you want higher precision, you just add more clocks to the relay to have the polygon tend to the circle.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 05/08/2020 04:25:07
The two theories do make identical predictions. Dave has a long history of creating straw man arguments against SR, such as the statement below:

That is incorrect. They make predictions that are mathematically distinct because LET's predictions are all conditional. It's a key difference. In LET it is incorrect to make those predictions in LET without the conditions. There are some predictions made by LET and STR which are identical because they always produce the same answers for all frames, such as those about the timings that will be made by clocks between passing one object and then later passing another.

Quote
LET makes conditional predictions (meaning that they're all predicated by "if this is the absolute frame") while STR makes absolute ones
On that note, it seems that if LET asserts that, then lacking a frame that satisfies the requirements of the interpretation, the interpretation must be false.

It doesn't lack such a frame - we just can't tell which one it is. You've moved on into such broken physics that I'm not going to bother commenting on it beyond saying that Spacetime generates event-meshing failures all over the shop: it's not sustainable science and it's being torn to shreds on Quora, the one place where it can be discussed properly without censorship. The establishment defenders simply have no moves to counter with: they've been fully exposed and found wanting.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 05/08/2020 04:43:13
The reality is that you're doing anti-education and it's unethical. You are pumping out disproved propaganda instead of doing real science. This is real science:-

Disproof 1

Imagine two objects moving at 0.5c relative to each other along a straight line. We introduce a pulse of light which moves along the same line at c relative to the first object. The speed of that light is 0.5c or 1.5c relative to the second object (depending on which direction along the line that object is moving in). STR denies that measurement and insists that the correct relative speed for the light and second object is c, but if the relative speed of the light to both objects is c, the two objects cannot be moving at 0.5c relative to each other: their relative speed to each other would have to be zero.

Whatís going on here? Well, Einstein bans you from accepting some measurements between light and objects that travel at lower speed than c. He requires you to change frame to make the second object stationary, and only then will he accept the relative speed for the light and that object. In that new frame, the relative speed between the light and the first object is now 1.5c or 0.5c, but again he bans you from accepting that measurement. So, he mixes frames to get the two measurements which he wants to make so that they conform to his bonkers theory, and he rejects all measurements that disagree with his ideology. In the course of changing frame, he changes the speed of the light relative to both objects. In doing so and mixing frames, he is making an illegal mathematical move.

Disproof 2

Picture an observer watching two ships in the distance which are passing each other, one moving towards him and the other moving away from him. The two ships each put out a flash of light at the moment when when they are side by side. These two flashes of light travel alongside each other all the way to the observer who sees them both arrive simultaneously. How did the two flashes of light know to travel at the same speed as each other? Did they decide to travel at c relative to one ship rather than the other ship? Did they decide to travel at c relative to the observer? They aren't going to know how the observer's moving until they reach him, so they can't do that. Also, we can have some of the light pass the first observer and be seen by a second observer further away who is moving relative to the first observer along the same line as all the rest of the action, so is the light supposed to move at c relative to that observer too?

Einstein would have you believe that the speed of the light is c relative to both observers, but that would mean the two observers couldn't be moving relative to each other. There could also be observers on the two ships who see the flashes pass them, and again Einstein wants the speed of that light to be c relative to them. He is trying to have an infinite number of contradictory things all happen at the same time. In reality, the speed of the light is c relative to the space fabric and needn't be c relative to any of the ships or observers at all. As soon as you deny the space fabric and its absolute frame, you lose the ability to govern the speed of the light from one flash to make it move at the same speed as the light from the other flash: each flash would have to travel at c relative to the ship that it was emitted from, so the light from one flash would reach the observer before the light from the other flash. Einstein's insistence that the speed of light is always c relative to any observer is nothing more than a contrived mathematical abstraction, and it breaks fundamental rules by tolerating contradictions - if he has the light move at c relative to all ships and observers, he has it moving at four speeds relative to itself. The big mystery here is how people can buy into Einstein's magical thinking and imagine that they're doing science.

So what do they do? Delete it. Move and hide it. Ban the real educators. That's what they do. That's what you do. It's immoral, and you can't get away with it forever.
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 05/08/2020 05:20:28
Einstein's insistence that the speed of light is always c relative to any observer is nothing more than a contrived mathematical abstraction

If that was true, then why have attempts to measure light's speed in a vacuum always resulted in c regardless of the technique we use?
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 05/08/2020 05:47:48
.
It doesn't lack such a frame - we just can't tell which one it is.
My argument has nothing to do with the ability to detect the correct frame. I'm saying there are no viable candidates from which to choose, so not knowing the correct answer on a multiple choice question becomes impossible if there are no available choices.
If you disagree, then give me a choice that works. You can't, for the reasons I explained above.

Quote
You've moved on into such broken physics that I'm not going to bother commenting on it beyond saying that Spacetime generates event-meshing failures all over the shop: it's not sustainable science and it's being torn to shreds on Quora, the one place where it can be discussed properly without censorship.
Further evidence then, since quora does indeed not censor nonsense. Tear the argument to shreds then, using whatever argument you found on quora. I've not seen any counter to it. If my argument has been presented (and disassembled) elsewhere, I'd be very interested in seeing it discussed, since so far I've seen nothing from anybody who knows their physics.
Title: Re: Is Special Relativity reciprocal?
Post by: alancalverd on 05/08/2020 12:40:19

The whole point of this example is that the circular motion is eliminated by the other clocks forming a relay race round the same circuit with them all moving along straight paths and confirming that the acceleration is irrelevant: it shows the case with acceleration to map with high precision to the case without acceleration, and if you want higher precision, you just add more clocks to the relay to have the polygon tend to the circle.
Oh dear.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 05/08/2020 17:24:43
Hi all,
here is a question for everybody.
A train observer on a train car with L'0=3.4641cs' sends a light beam towards the front of the train car.
Is the light beam going to cross 3.4641cs' in 3s' of the train reference frame?
Jano

(https://i.imgur.com/xnvV6D2.png)
Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 05/08/2020 18:42:00
@David Cooper
David, donít have a problem with you discussing LET vs SR, but as you know we do segregate new/alternative theories so Iíll move this to allow full discussion.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 05/08/2020 18:53:53
Colin,
this thread is not about LET.
Why did you move it?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 05/08/2020 20:19:08
Colin,
this thread is not about LET.
Why did you move it?
Jano
The OP is enough for that (the part in bold).  OK, it was worded as a question, not as an assertion, but you're not open to pretty much a unanimous answer to the question, so it seems best that this thread is here.

Length contraction being real or not depends on one's definition of 'real'.  Is 5 being closer to 7 than to 2 'real'?  Ambiguous question without a definition, but 5 seems by any reasonable line of thinking to actually be closer to 7 than to 2, so I'd generally guess 'yes'.

Similarly, length contraction is real because if it were not, different measurements would result, such at the time it takes light to traverse to the end of a moving object and back. But that's using my definition of 'real'.

I do agree that it is your thread and not about LET, so not sure why the title needed to be changed.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 05/08/2020 20:38:06
This is the definition of reciprocal in my view.
Do we have an agreement?
No, we do not. Your diagram doesnít make sense, nor does it define reciprocal.


Colin,
Please, fix the subject of the thread.

(https://i.imgur.com/L6PbNmo.png)

Fair enough, here is a description.
The left origin of the blue arrows is an event A where x=x'=0 and t=t'=0.
2s in platform frame are required for the red arrow up 90 degree.
... but 1s for the blue arrow to go up 90 degree.
This is the relativity, right?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: puppypower on 05/08/2020 21:28:23
I invented an exercise regimen called the Special Relativity Work Out; SRWO, about 10 years ago. This patent pending exercise regimen is a way to burn calories, like you are exercising, but without exercising. it is based on a relative reference effect often used when discussing SR and the universe. 

The way it works is my company has a professional runner on staff, who runs around a track. The paying clients recline in chairs, at various points along the track. I then hypnotize them and have them all pretend that the pro runner is stationary, and we are all moving, I have them more their arms. Since reference is relative to the observer, and there is no preferred reference, all the clients are now in relative motion without having to actually move. They burn calories. The runner by being stationary, burns much fewer calories, base on the consensus of the majority reference. This allows him to run for hours without getting tired. I feed him one grape per hour.

This exercise regimen is used throughout astral physics, where we are told reference is relative to observer and there is no preferred or no absolute runner reference in the universe. The SRWO i backed by physics.

The reason this premise can work in physics is we see the universe based on visual or light-energy type evidence. We cannot touch the materials of the universe, like the mass of a distinct galaxy. But we can see its various lights and infer things from that based on our relative reference.  Based on this scientific approach, I place the chairs around the track, so the clients  can see the runner's light emissions, but they cannot touch the runner either. Since physics says this result in no preferred reference, everyone burns calories just for showing up and believing. I have applied for an intergalactic patent pending.

When Einstein developed SR he purposely used three parameters, mass, distance and time. Mass is the only tangible thing among the three parameters. If I throw a rock of mass=M at you, it will hurt. Mass via GR can bend space and time.

Distance and time are more like reference variables. I cannot throw distance or time at you and make it hurt. It is more in the mind and imagination game. Since the mass, which is the  only real substance is left out, by default, since the energy signals come to us faster and are easier to use, we only use two of the three SR variable and infer the masa and relativistic mass. We cannot do a proper energy balance without the actual tangible mass. The mass would give us the preferred reference sequence by allowing us to compare relative reference claims via an energy balance of the substance that emits the light.

This science support is why the SRWO is such a success; backed by science.
Title: Re: Is Special Relativity reciprocal?
Post by: xersanozgen on 05/08/2020 21:44:05
 Reciprocity principle works for classic and special relativity.

If we consider the twin event in space condition, A and B have their own speeds; and we may choose any one for reference frame. The relative speed will be Va + Vb.

And when they meet again, they will seem/become at the same age.
Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 05/08/2020 21:46:37
Colin,
Please, fix the subject of the thread.

(https://i.imgur.com/L6PbNmo.png)

Fair enough, here is a description.
The left origin of the blue arrows is an event A where x=x'=0 and t=t'=0.
2s in platform frame are required for the red arrow up 90 degree.
... but 1s for the blue arrow to go up 90 degree.
This is the relativity, right?
Jano
Sorry, forgot David is not OP, although he does appear to want to put this into LET vs SR territory.

The diagram is not self explanatory and certainly doesnít define reciprocal.

I suspect by reciprocal you mean the type of symmetry described in your previous post which is closer to a definition:
Two inertial observers see each other clocks going slower.
Two inertial observers see each other Lorentz Contracted.
Whatever the first inertial observer can say about the second one then the second observer can say the same things about the first one.

This reciprocity/symmetry is not a problem in relativity despite your objections.

If you go back to Einsteinís original paper, which you quoted, you will see that symmetry is essential to his argument. He was addressing a topical problem of the time and points out that whether the wire is moving or the magnet is moving is relative and can be viewed from the frame of either the wire or the magnet. Both observers (wire frame or magnet frame) will agree on a very real effect, a current is induced in the wire. The consequence of viewing things this way is that electrodynamics is unified with Galilean mechanics and laws of both physics are independent of the inertial frame of reference. Length contraction and time dilation are a consequence of this.

I invented an exercise regimen called the Special Relativity Work Out; SRWO, about 10 years ago. ......
I really donít see the relevance of this post to this thread. I intend to remove it unless the OP objects
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 05/08/2020 21:51:59
Einstein's insistence that the speed of light is always c relative to any observer is nothing more than a contrived mathematical abstraction

If that was true, then why have attempts to measure light's speed in a vacuum always resulted in c regardless of the technique we use?

All attempts to measure the speed of light through the space fabric (without taking into account slowing due to depth in gravity wells) gives us the value c. The key part of your quote which you appear to have missed was the bit saying "relative to". When you attempt to measure the speed of light in a specific direction relative to yourself (an observer with a measuring apparatus of some kind), you can get any value from a fraction above zero to a fraction below 2c. If you program into the experiment the assumption that the apparatus is stationary, then you will measure the speed of light relative to the apparatus to be c. If you program a different assumption such as that the apparatus is moving at 0.5c, then you will measure the speed of light relative to the apparatus to be 0.5c in one direction, 1.5c in the opposite direction, and the full range of possible speeds between 0.5c and 1.5c for the directions in between. These results can be measured, but because the initial assumption determines the end result, the measurements aren't useful.

However, the establishment is happy to make measurements that program in the assumption that the apparatus is stationary and to point at the result ("See - the speed of the light is c relative to us") as if it's confirmation of their belief, while they reject any experiment made with a different starting assumption even though those experiments carry exactly the same weight. The establishment is happy to train up large numbers of people to go around spreading misinformation by asserting that experiments always measure the speed of light relative to the observer to be c, but for every measurement you can make for that which give you the answer c, there are an infinite number of other measurements you can make which are equally valid which give you answers that aren't c, ranging from nearly zero to nearly 2c.

Science should not be doing propaganda. Once the idea that experiments always measure the speed of light as c relative to any observer has been debunked, it should not keep being put back on the table.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 05/08/2020 22:40:17
Hi all,
here is a question for everybody.
A train observer on a train car with L'0=3.4641cs' sends a light beam towards the front of the train car.
Is the light beam going to cross 3.4641cs' in 3s' of the train reference frame?
Jano

(https://i.imgur.com/xnvV6D2.png)


If it is not a problem then how do we explain this?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 05/08/2020 22:48:30
My argument has nothing to do with the ability to detect the correct frame. I'm saying there are no viable candidates from which to choose, so not knowing the correct answer on a multiple choice question becomes impossible if there are no available choices.
If you disagree, then give me a choice that works. You can't, for the reasons I explained above.

(1) In an expanding universe with three space dimensions existing within the surface layer of an expanding or contracting 4D bubble, the absolute frame can't coincide with a frame within the 3D universe. What you would have instead is a pseudo-absolute 3D frame at any given point in the 3D universe which has the speed of light travel at c relative to it in every direction, while every other frame at that location has light travel faster through it in one direction than the opposite way. In such a situation, every point in that 3D universe could have a different pseudo-absolute frame.

(2) In an expanding universe with three space dimensions expanding within a 3D superspace external to the universe, there will be an absolute frame in the universe which is the same frame as the absolute frame in the superspace which the universe expands in, but clearly for the expansion of the universe to happen, the superspace must allow parts of the universe to move faster than c through the superspace, so it isn't the same kind of frame. Again though, there will be different pseudo-absolute frames in that universe at different locations. A pseudo-absolute frame is always a frame at a specific location where the speed of light is c relative to that location in all directions.

(3) In an expanding universe with three space dimensions magically expanding in nothing with no outer anywhere to have an absolute frame, we are left with pseudo-absolute frames at every point in the universe which in the absence of an external anything become a bit more absolute than they would otherwise be, but again we have an absolute frame that's a different frame for each location.

These are complications, but for normal purposes we can ignore them and just talk about an absolute frame within a region of space in which the speed of light relative to that frame is c in every direction. Any frame could, for all we know, be that absolute frame. You claim there are no viable choices. I say there are an infinite number of viable choices. Disproof 1 and disproof 2 (which I posted here last night) confirm that there must be such an absolute frame.


Quote
Tear the argument to shreds then, using whatever argument you found on quora. I've not seen any counter to it. If my argument has been presented (and disassembled) elsewhere, I'd be very interested in seeing it discussed, since so far I've seen nothing from anybody who knows their physics.

I didn't find it on Quora. I put it there. Event-meshing failures were my discovery when I tried to simulate Spacetime models by their own rules and found that they don't work correctly. By Spacetime, I refer to pure Spacetime models which claim that there is no absolute/Newtonian time in the model - it's possible to make impure Spacetime models work by adding absolute time to them, but the establishments models ban that. While they ban it though, every single simulation they have that purports to be of their Spacetime models has absolute/Newtonian/computer time added to it to hide the event-meshing failures.

Twins Paradox - the gravity version:-

Let's look at the gravity version of the twins paradox where movement is practically eliminated (tending to zero the longer we run the experiment). Twin A stays high above a black hole. Twin B is let down near to the black hole on a long cable and hovers over it near the event horizon. After a year, twin B is brought back up again to be reunited with twin A. When they separated they were both five years old. Twin A is now 55, and twin B is 10.

What happened? The twins were separated at Spacetime location S (S for separation) and were later reunited at Spacetime location R (R for reunion). Twin A followed a path through Spacetime which was of 50 years length.Twin B followed a path through Spacetime which was only of 5 years length. There is only one kind of time in the model so there is no means for the time of either of these paths to tick slow: they will just tick at the rate of time, which means that twin B will reach location R and find an event-meshing failure: twin A cannot meet him there because she is only one tenth of the way from S to R.

That's your broken model. Your simulations all cheat by adding a kind of time that is not the time dimension, but which governs the ticking rate of the time of the time dimension in such a way as to make twin B's clock tick at a tenth the rate of twin A's clock. That mechanism is explicitly banned in the model though, so passing these models off as GTR is fraud.

They have no answers. I show them how broken their model is and ask them to show me a simulation of their model which doesn't cheat in this way and which doesn't generate an event-meshing failure with the gravity version of the twins paradox. They have PhDs falling out of their backsides, but they can't do it. They just go silent. And they can't do it because it's mathematically impossible: the universe can't do it either.

The eternal static block universe idea doesn't help either as it destroys causation, turning it into apparent causation instead with an amount of luck tied up in it which the description astronomical to the power of a googolplex barely begins to hint at. If time doesn't run and the block isn't built in order of causation, you don't have any causation there. Trying to stop time being a running process kills causation and merely takes you from one bankrupt model to another bankrupt model with no functionality at all.

Spacetime's a disproved idea, shown to be wrong by experiments which don't produce the event-meshing failures which Spacetime models actually predict (when you run them strictly by their own rules without cheating). If you want to go on smuggling in absolute/Newtonian/computer time to hide the event-meshing failures, you should own up to it and admit that you've got absolute time in the model too, and that absolute time is the real time in the model while the "time" dimension is relegated to being nothing more than an unusual type of space dimension. And once you've done that, you can apply Occam's razor to the thing and reject it by saying that LET accounts for all the same observations and experiments with the same precision in an enormously simpler way with Euclidean geometry.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 05/08/2020 22:49:46

The whole point of this example is that the circular motion is eliminated by the other clocks forming a relay race round the same circuit with them all moving along straight paths and confirming that the acceleration is irrelevant: it shows the case with acceleration to map with high precision to the case without acceleration, and if you want higher precision, you just add more clocks to the relay to have the polygon tend to the circle.
Oh dear.
Exactly. Glad you've seen your error at last.
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 06/08/2020 00:27:31
The way it works is my company has a professional runner on staff, who runs around a track. The paying clients recline in chairs, at various points along the track. I then hypnotize them and have them all pretend that the pro runner is stationary, and we are all moving, I have them more their arms. Since reference is relative to the observer, and there is no preferred reference, all the clients are now in relative motion without having to actually move. They burn calories. The runner by being stationary, burns much fewer calories, base on the consensus of the majority reference. This allows him to run for hours without getting tired. I feed him one grape per hour.

Congratulations on misunderstanding relativity. The fact that the runner is moving relative to the person sitting in the chair is not what makes them burn calories (a person running on a treadmill isn't moving either, but they are still burning calories). What makes the runner burn calories is, in large part, from the rhythmic contraction of their body's muscles. The muscles will be seen as contracting and extending in any reference frame. Some of the calories burned might also come from wind resistance (which, again, will be seen in any reference frame), but that's probably a minor component.
Title: Re: Is Special Relativity reciprocal?
Post by: alancalverd on 06/08/2020 00:48:51
Exactly. Glad you've seen your error at last.
No. I've seen yours.

If two bodies are travelling at the same speed along two different tangents to a circle, they are not travelling at the same velocity. Velocity is a vector, and acceleration is the rate of change of velocity.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 06/08/2020 00:56:30
Colin,
Please, fix the subject of the thread.

(https://i.imgur.com/L6PbNmo.png)

Fair enough, here is a description.
The left origin of the blue arrows is an event A where x=x'=0 and t=t'=0.
2s in platform frame are required for the red arrow up 90 degree.
... but 1s for the blue arrow to go up 90 degree.
This is the relativity, right?
Jano
Sorry, forgot David is not OP, although he does appear to want to put this into LET vs SR territory.

The diagram is not self explanatory and certainly doesnít define reciprocal.

I suspect by reciprocal you mean the type of symmetry described in your previous post which is closer to a definition:
Two inertial observers see each other clocks going slower.
Two inertial observers see each other Lorentz Contracted.
Whatever the first inertial observer can say about the second one then the second observer can say the same things about the first one.

This reciprocity/symmetry is not a problem in relativity despite your objections.
...

If it is not a problem, please, explain this as well:

(https://i.imgur.com/QbyqCQl.png)

Thanks,
Jano

Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 06/08/2020 00:57:24

(https://i.imgur.com/C4TkonR.png)

Kryptid,
Question, how is it possible that when the travelling twin is in 'the same reference' frame, has almost 0 relative speed there are the biggest proper time deltas between the reference frames?
Please, see the blue lines.
Do you agree that this does not make sense?
Jano

How about this one?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 06/08/2020 01:01:24
Colin,
Saying that reciprocity/symmetry is not a problem without backing it up is not very useful,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 06/08/2020 05:08:39

(1) In an expanding universe with three space dimensions existing within the surface layer of an expanding or contracting 4D bubble, the absolute frame can't coincide with a frame within the 3D universe. What you would have instead is a pseudo-absolute 3D frame at any given point in the 3D universe which has the speed of light travel at c relative to it in every direction, while every other frame at that location has light travel faster through it in one direction than the opposite way. In such a situation, every point in that 3D universe could have a different pseudo-absolute frame.
I think youíre attempting to describe the comoving coordinate system, but without knowing the terminology.  This solves the problem of any inertial frame failing to map distance places.  Using such a coordinate system, one can speak of hypothetical objects at any distance and recession rate. This is indeed the one frame of choice for the typical absolutist theory, and it is even detetable. Earth is currently on a slow day and is moving at somewhere around 400 km/sec in this frame.

 But the coordinate system fails for the black hole case. It does not foliate spacetime within the event horizon, and thus cannot be used to answer my example pair of event in the earlier post.
Thus the system is not a valid candidate for the absolute frame.  A person inside the event horizon, who presumes that system to be the absolute frame, cannot answer the question Ďwhat actual time is it now?í, and that question should always be answerable if an actual absolute event ordering exists. If there are multiple viable candidate coordinate systems, then sure, one cannot know which is the correct one, but if there are no viable candidates, then there can be no absolute foliation, and any theory like LET that posits such an ordering is necessarily false.

Iíve floated this argument at a few forums, but of the people that know enough of their relativity to comprehend the argument, I get a vague ďI guess soĒ because none of them are absolutists and thus donít find the argument to threaten their view. Most of the absolutists donít know their physics for beans, so it doesnít threaten their view either. Youíre one of the few from whom I was hoping for an intelligent response. I have no idea if my argument is flawed. I want it taken apart since Iíve started threads defending the absolutist view against relativity. But thatís before I thought of this argument. All attempts to disprove absolutism seem flawed. Surely Iíve not discovered a valid one.

Quote
(2) In an expanding universe with three space dimensions expanding within a 3D superspace external to the universe, there will be an absolute frame in the universe which is the same frame as the absolute frame in the superspace which the universe expands in, but clearly for the expansion of the universe to happen, the superspace must allow parts of the universe to move faster than c through the superspace so it isn't the same kind of frame.
Um, this sounds like a theory of the universe expanding from one location into pre-existing empty space. If so, this view is not held by anybody as it can be readily falsified. It predicts an absence of the CMB except possibly from the one point at which the big bang occurred.  Option 3 seems to be something of the same thing. Hard to tell the difference from your description.
No, I want actual viable physics, but with the addition of a preferred foliation.


Quote
These are complications, but for normal purposes we can ignore them and just talk about an absolute frame within a region of space in which the speed of light relative to that frame is c in every direction.
Sure, it always works locally, even for the guy in the black hole. That doesnít aid him in asking what time it is.

Quote
You claim there are no viable choices. I say there are an infinite number of viable choices. Disproof 1 and disproof 2 (which I posted here last night) confirm that there must be such an absolute frame.
Those?  I wasnít going to bother commenting on them. You either donít know relativity theory or youíre deliberately misrepresenting it. Youíve proven nothing with this tired strawman argument. Weíve been over this. If you donít know your relativity, then you probably cannot defend absolutism from my argument. I need somebody who knows their physics, not somebody who mangles it for personal purposes.

Sorry to have wasted your time.

Quote
I didn't find it on Quora. I put it there.
Figures. My opinion of quora is unchanged then.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 06/08/2020 11:01:37
Hi all,
here is a question for everybody.
A train observer on a train car with L'0=3.4641cs' sends a light beam towards the front of the train car.
Is the light beam going to cross 3.4641cs' in 3s' of the train reference frame?
Jano

(https://i.imgur.com/xnvV6D2.png)


If it is not a problem then how do we explain this?
Jano
Let's ignore this one, I have made a mistake here.
The triplet paradox and the twin paradox explanation, those I'd like to discuss,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 06/08/2020 23:45:27
Exactly. Glad you've seen your error at last.
No. I've seen yours.

If two bodies are travelling at the same speed along two different tangents to a circle, they are not travelling at the same velocity. Velocity is a vector, and acceleration is the rate of change of velocity.

There is a method for calculating π which involves using polygons. You use more and more sides for the polygons and you get a value closer and closer to π. As you use more and more of them, it doesn't tend to half π or twice π, or a tenth of π, or a thousand times π, but to π. This approach is well understood by mathematicians, and it's the same approach that I'm using here.The red clock ticks half as often as the white clock. I can up the speed of travel though and make it tick a thousandth as often, or a millionth, and I can put millions of clocks on tangents to the red clock's path and produce ever-greater precision in matching up their timings for parts of the circuit.They show that the red clock is ticking at the rate it's ticking at because it's moving at as near as makes no difference the same rate as the clock on a tangent that's accompanying it at that moment.

Furthermore, we can put lots of extra clocks in on other paths similar to the red clock and its accompanying clock on a tangent to make our extra clocks close off all possible ways that we might be being misled by those measurements. We can have some go slightly faster and others go slightly slower, and we can create a cage of measurements all round what the red clock is doing that show that all the clocks in that set are ticking at practically the same rate. You have a microscopic amount of wriggle room there and it does not help you one jot.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 06/08/2020 23:47:52
The triplet paradox and the twin paradox explanation, those I'd like to discuss,
Jano

I'd be happy do discuss them, but can't make sense of what they are from the way you've worded them.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 07/08/2020 00:21:44
But the coordinate system fails for the black hole case. It does not foliate spacetime within the event horizon, and thus cannot be used to answer my example pair of event in the earlier post.

The failure in the black hole case is caused by the theory your using to define the geometry of your black hole. In LET, there is Euclidean geometry and absolute time, so the problems caused by the contrived Spacetime mathematical abstraction don't occur. With black holes in GTR, you have multiple impossibilities: the singularity cannot govern the shape, size or location of its gravity well because it can't get any signals out to it. If it accelerates, its gravity well should be left behind, but you just break the rules and have them move together regardless. It's a broken mess. You can't use your broken mess to disprove a theory that doesn't have that broken mess.

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Thus the system is not a valid candidate for the absolute frame.  A person inside the event horizon, who presumes that system to be the absolute frame, cannot answer the question Ďwhat actual time is it now?í, and that question should always be answerable if an actual absolute event ordering exists. If there are multiple viable candidate coordinate systems, then sure, one cannot know which is the correct one, but if there are no viable candidates, then there can be no absolute foliation, and any theory like LET that posits such an ordering is necessarily false.

In LET, you can't cross the event horizon and there is no singularity: a black hole is a ball of dense stuff: you slow to a halt at the outer edge and the event horizon can then migrate out past you as you push the local energy density up. In string theory too, you stop at the event horizon of the fuzzball and there is no singularity. In quantum mechanics too, I hear things about things stopping at the event horizon rather than crossing it. I wonder which theory will have to be given the push in order to unite the rest.

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Youíre one of the few from whom I was hoping for an intelligent response. I have no idea if my argument is flawed. I want it taken apart since Iíve started threads defending the absolutist view against relativity. But thatís before I thought of this argument. All attempts to disprove absolutism seem flawed. Surely Iíve not discovered a valid one.

Well, not only are you basing it on broken ideas about the interior of black holes, but you're using a model that also invalidates itself with event-meshing failures. I explained those in my previous post, but I don't think it gets through when expressed in mere words, so I'm writing it as a program for you (armed with a new technique which I've developed to get round the design flaws of SVG graphics to stop my code breaking every time a browser is updated). It's more than half done, so it should be up by tomorrow. There are better theories that need to be worked on: if a thousandth as much work had been done on LET as has been done on GTR, we would be far ahead of where we are with physics today. Broken theories are the wrong analysis tools.

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Um, this sounds like a theory of the universe expanding from one location into pre-existing empty space.

Indeed it is: (1), (2) and (3) are covering different possible realities, only one of which at most will be the actuality. The point I was making is that it's hard to have a perfect definition of the absolute frame because of these complications, but we can have something that we call an absolute frame in normal cases even if it technically isn't one. Such an absolute frame can vary between different locations, but what is always true of it is that the speed of light is c in every direction relative to an object which is stationary in the absolute frame at a given location. STR denies that there is such a thing because it asserts that all frames have that property, but STR disproofs 1 and 2 (see further up the thread - previous page) show STR to be wrong about that. Disproof 3 also shows that the Michelson-Gale-Pearson experiment showed experimentally that the speed of light relative to different observers must vary:-

Disproof 3

There were experiments which disproved Einstein's STR a century ago. The Michelson-Gale-Pearson is one of those, though it wasn't recognised as such at the time. It is only today with greater minds than Einstein looking at the evidence that we can see what this experiment actually revealed. Two lots of light were sent round a rotating ring, and one lot of light returned to the emitter before the other, just as it does in the Sagnac experiment. The light that travelled in a clockwise direction passed all the material of the ring at a higher speed on average relative to that material while local to it than the light travelling the opposite way. This is observed to be the case by observers in all reference frames so it is beyond dispute. The length contraction on the ring is the same in both directions, so it clearly destroys Einstein's assertion that the speed of light is always c relative to any observer - we can put observers all round the ring, each one moving with their local part of the ring, and we know that the speed of light must be passing some of them at speeds other than c relative to them.

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You claim there are no viable choices. I say there are an infinite number of viable choices. Disproof 1 and disproof 2 (which I posted here last night) confirm that there must be such an absolute frame.
Those?  I wasnít going to bother commenting on them. You either donít know relativity theory or youíre deliberately misrepresenting it. Youíve proven nothing with this tired strawman argument. Weíve been over this. If you donít know your relativity, then you probably cannot defend absolutism from my argument. I need somebody who knows their physics, not somebody who mangles it for personal purposes.

There's nothing mangled about it and there are no personal purposes involved. I analyse things in a search for truth and not to back up my beliefs. I try to destroy my beliefs by testing them to destruction. I've been unable to do that here though because it it's STR that falls to pieces here. You are simply allowing your beliefs to override your ability to reason on these points. STR makes illegal moves there which no competent mathematician accepts - they just bite their lip and shake their head, not speaking out because they don't want to become targets of abuse from the mob. And what I'm getting from physicists in emails when they're pushed into a corner is outright rejection of mathematics. They think they're above it.
Title: Re: Is Special Relativity reciprocal?
Post by: xersanozgen on 07/08/2020 11:06:21
(https://i.hizliresim.com/TvwQMH.jpg) (https://hizliresim.com/TvwQMH)

In their first meeting astronout A will say to B "Your clock has been lost 2 hours". Also Astronout B will answer: "Your clock has been lost 2 hours too".

In their second meeting A  will say " your clock has been lost 4 hours" B will  answer the same,

....

against causality.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 07/08/2020 21:01:35
The failure in the black hole case is caused by the theory your using to define the geometry of your black hole.
My point exactly. Iím using something like LET and other preferred foliation theories.  The failure of the black hole case is indeed caused by the failing of that theory.

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In LET, there is Euclidean geometry and absolute time, so the problems caused by the contrived Spacetime mathematical abstraction don't occur.
Thatís a different geometry than the one I typically see claimed by etherists, but fine.  Euclidean geometry it is.

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In LET, you can't cross the event horizon and there is no singularity: a black hole is a ball of dense stuff: you slow to a halt at the outer edge and the event horizon can then migrate out past you as you push the local energy density up.
If thereís no singularity, then why canít you get past it? Events beyond it donít exist in your Euclidean geometry.  This is exactly my point. Choose a geometry where the mathematical singularity vanishes (such as the local frame of somebody falling in) and there is no singularity at all.  One passes in without a hitch, but cannot answer the question what time it is far away.  He can see his old home, so itís not like heís exited the universe or anything, but he canít get back to that home any more than you can get back to any event you see.

A mathematical singularity isnít any kind of magical physical thing. Itís just an abstract artifact of a chosen coordinate system, and it is a mistake to consider such abstractions to have physical meaning.  The singularity at the center of a black hole is a physical one, not abstract at all, but youíre denying the existence of that since it isnít in the part of spacetime foliated by your chosen Euclidean coordinate system.

An example of an abstract mathematical event horizon is the Rindler horizon.  From the accelerated reference frame of an observer accelerating at a continuous 10g, the event horizon exists about 920 billion km behind him.  That means that if he drops his passenger (with a clock) out of his window, that passenger will fall to that event horizon and freeze in time shy of its surface, and even evaporate away with a version of Hawking radiation.  From the point of view of the passenger in free-fall, he takes no notice when this horizon passes him by. I know, because I've done it multiple times, compliments of expansion of space.  The only thing that changes upon crossing said horizon is that any signal he sends back to the accelerating guy will never reach him. Thatís the exact kind of thing that happens with black holes. No high-density collection of stuff at the surface. Itís life as normal from this alternate point of view. Mathematical singularities are not physical singularities.

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Disproof 3

There were experiments which disproved Einstein's STR a century ago. The Michelson-Gale-Pearson is one of those, though it wasn't recognised as such at the time. It is only today with greater minds than Einstein looking at the evidence that we can see what this experiment actually revealed. Two lots of light were sent round a rotating ring, and one lot of light returned to the emitter before the other, just as it does in the Sagnac experiment. The light that travelled in a clockwise direction passed all the material of the ring at a higher speed on average relative to that material while local to it than the light travelling the opposite way. This is observed to be the case by observers in all reference frames so it is beyond dispute.
SR predicts this, or at least the Sagnac effect. How is this MGP experiment distinct from that?

You need to get your physics from legit science sites and not from quack denial sites. Citation needed.
Title: Re: Is Special Relativity reciprocal?
Post by: evan_au on 08/08/2020 01:13:00
Quote from: Halc
From the accelerated reference frame of an observer accelerating at a continuous 10g
I'm not volunteering to be the observer in that experiment!
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 08/08/2020 06:30:07
The failure in the black hole case is caused by the theory your using to define the geometry of your black hole.
My point exactly. Iím using something like LET and other preferred foliation theories.  The failure of the black hole case is indeed caused by the failing of that theory.

It isn't LET that's creating a mess in black holes. If you're working with theories that can't handle time correctly, throw them in the bin where they belong. Anything that has time run at different rates for different objects breaks by generating event-meshing failures and immediately disqualifies itself from science.

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In LET, you can't cross the event horizon and there is no singularity: a black hole is a ball of dense stuff: you slow to a halt at the outer edge and the event horizon can then migrate out past you as you push the local energy density up.
If thereís no singularity, then why canít you get past it? Events beyond it donít exist in your Euclidean geometry.

Not being able to get past it doesn't mean there are no events further in. Once the energy density reaches a certain level, the speed of light is reduced to zero (relative to the black hole rather than to the space fabric), so anything falling to the event horizon simply slows down and stops by the event horizon. All objects are made out of waves of energy bound by the same limit, and when that limit is zero, they halt. That's how they get trapped when they reach the event horizon, and it's also what stops them moving further in. Stuff that got in there earlier does exist further in though, and there's stuff all the way to the centre. There aren't a lot of events in there because the action's frozen, but time is still passing for all that stuff regardless, just as it is for the food in your freezer that isn't rotting.

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This is exactly my point. Choose a geometry where the mathematical singularity vanishes (such as the local frame of somebody falling in) and there is no singularity at all.  One passes in without a hitch, but cannot answer the question what time it is far away.  He can see his old home, so itís not like heís exited the universe or anything, but he canít get back to that home any more than you can get back to any event you see.

Your whole view of what goes on in a black hole is dictated by the predictions of a broken model in which the event horizon can be crossed. In GTR, if you're suspended by the event horizon, you don't see your old home because "time" stops for you, but for someone else falling across the event horizon, it isn't, so they can see out. It isn't like that in LET: there is no falling across the event horizon and there is no seeing out from the event horizon either; not because new images of the outside aren't able to get there, but because your functionality freezes and you can't process any images.

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An example of an abstract mathematical event horizon is the Rindler horizon.  From the accelerated reference frame of an observer accelerating at a continuous 10g, the event horizon exists about 920 billion km behind him.  That means that if he drops his passenger (with a clock) out of his window, that passenger will fall to that event horizon and freeze in time shy of its surface, and even evaporate away with a version of Hawking radiation.  From the point of view of the passenger in free-fall, he takes no notice when this horizon passes him by. I know, because I've done it multiple times, compliments of expansion of space.  The only thing that changes upon crossing said horizon is that any signal he sends back to the accelerating guy will never reach him. Thatís the exact kind of thing that happens with black holes. No high-density collection of stuff at the surface. Itís life as normal from this alternate point of view. Mathematical singularities are not physical singularities.

Again that's just nonsense generated by a broken model. Your problem is that Spacetime is incompetent: time cannot vary for different objects because that would generate event-meshing failures, and no such failures are ever seen in the real universe.

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Disproof 3

There were experiments which disproved Einstein's STR a century ago. The Michelson-Gale-Pearson is one of those, though it wasn't recognised as such at the time. It is only today with greater minds than Einstein looking at the evidence that we can see what this experiment actually revealed. Two lots of light were sent round a rotating ring, and one lot of light returned to the emitter before the other, just as it does in the Sagnac experiment. The light that travelled in a clockwise direction passed all the material of the ring at a higher speed on average relative to that material while local to it than the light travelling the opposite way. This is observed to be the case by observers in all reference frames so it is beyond dispute.
SR predicts this, or at least the Sagnac effect. How is this MGP experiment distinct from that?

You need to get your physics from legit science sites and not from quack denial sites. Citation needed.

I got it by analysing the experiment: not by taking anything from quack sites. It's a mathematical proof. All observers get the same timing difference. All observers measure the length of the material to be the same in both directions. All competent mathematicians (and high-school maths teachers too) can confirm its validity.

I'll edit a link in here in a few minutes once I've uploaded the program that compares simulations and show GTR generating event-meshing failures alongside the fake version of GTR used in all the simulations that purport to be of GTR but which cheat by smuggling in absolute time...

It isn't finished yet, but there's enough there to get started, so here it is: magicschoolbook.com/science/Event-Meshing-Failures.html (http://magicschoolbook.com/science/Event-Meshing-Failures.html). I haven't got the clocks displayed yet (and it also lacks the write-up that will end up underneath it later). Note that if you don't press any buttons after starting it running, it moves the blue twin next to the black hole automatically in the year 2025 and automatically brings him back too in 2075. He ages 25 years while the red twin ages 50 years. After you've moved him manually, the automatic moves no longer occur - they're just there to make sure people see something useful happen on the first run. Notice the event-meshing failures in the GTR simulation which don't happen in the pseudo-GTR sim: the blue twin reaches the reunion point before his sister is there, so they cannot interact with each other at all there. By the time she catches up, he's still not there because he's moved on ahead, although if you're using a block universe, he can leave a fossil of himself there which she can interact with, and in doing so she will change events, but that's another issue. We actually see form the GTR sim that events change at individual Spacetime locations anyway because objects that pass through those points can't all arrive there simultaneously, so it's even more broken in that it still has to have another kind of time in it to enable that to happen. It is simply not possible to have a pure Spacetime model with running time and real causation.

The key part of the code is at the top of the function called "run()" which is run 20 times a second, and I'll put a copy of that here for you now:-

comptime=comptime+1;  // Count interval timer ticks.

// We do the GTR simulation first:-

rt=rt+1;  // Advance red twin up the screen every time by adding one to its altitude - this handles it for both simulations

if(ts!=1){bt1=bt1+1}  // Do the same for blue twin if he is right next to red twin.

if(ts==1){bt1=bt1+1/pld1}  // but if blue twin's next to the black hole, add the reciprocal of the path length difference factor - we do this because we're dealing with non-Euclidean geometry, so we have to advance him up the screen faster while his clock ticks at the full rate of the only kind of time that exists in the model.

bh1=bh1+1/pld2;  // We do the same kind of thing with the black hole, and it immediately puts it way beyond the top of the screen on the first move.

// We do the pseudo-GTR simulation now, but we can use rt for both simulations with the red twin as they behave the same way in both models as she's essentially out of the gravity well (feel free to quibble about that if you like - fixing the small difference involved won't help you), so there are only two more objects to handle:-

if(ts==0 || ts==3){bt2=bt2+1}  // We do the same for blue twin as red twin while they're side by side

if(ts==1 || ts==2){bt2=bt2+(1/pld1)*pld1}  // But if the blue twin's next to the black hole, we add the reciprocal of the path length difference factor, but then multiply the result by pld1 to make the proper time tick slow so that the blue twin doesn't get ahead of the red twin. This is where computer time governs the tick rate of any proper time to prevent it generating event-meshing failures (because computer time has to exist at all locations for all objects in order for the proper time of objects to be compared with it and adjusted to run slow to the right degree relative to it), but that breaks the rules of GTR because the computer time in such circumstances serves as absolute time.

bh2=bh2+(1/pld2)*pld2;  // Do the equivalent for the black hole so that it can't get ahead either.


So, the challenge for you (and all other defenders of the broken model) is to make a simulation like these two, but you have to produce the appearance of the second simulation in order to avoid the event-meshing failures, but without cheating by using absolute time as a control mechanism to slow the ticking of the blue twin's proper time under the governance of that absolute time which is banned in the GTR model. So how do you make the proper time tick slow? Does it just tick slow by magically knowing how much slower to tick without reference to any other time?
Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 08/08/2020 08:54:34
Distance and time are more like reference variables. I cannot throw distance or time at you and make it hurt.
If you fall 1m it might hurt, if you fall 100m you wonít feel it - ever again. If I lock you up for 1 month that is an inconvenience, for 100 years itís life changing.

Colin,
Saying that reciprocity/symmetry is not a problem without backing it up is not very useful,
Jano
I did back it up, but I will expand.
You read Einsteinís electrodynamics paper, he mentions the asymmetry in viewing a moving magnet or a moving wire which is not resolved using Galilean transforms, nor is the problem of transforming Maxwellís laws; but these are resolved using Einsteinís proposals. It results in some symmetries of time dilation and length contraction from the perspective of different observers; is this a problem?
We are all familiar with the Galilean transforms which allow us to transform Newtonís laws of motion to the perspective of (slow) moving observers, they also results in some symmetries, which Iím sure I donít need to spell out. Those symmetries donít cause problems if you understand Galilean relativity and are clear which frame you are taking measurements from, similarly the SR transforms donít cause problems.

There are 2 big questions: are the effects real, is there an alternative?

If by real we mean can be subject to objective measurements, then SR/GR pass as real effects and there is plenty of evidence from particle accelerators, NIST experiments, gravity probes, etc.

Is there an alternative? Well, David is proposing one.

I donít see much point in you going over old ground with the SR scenarios, which have been done to death. The bigger question is whether you can take the electrodynamics paper and propose a rigorous alternative which allows accurate transforms and aligns with observations that the laws of electromagnetism are not frame dependent. The big outcome from the electrodynamics paper was the proposal that electric and magnetic fields are not separate, but are different aspects of a single electromagnetic field, can you preserve this or do you have a different proposal. Iím not aware David has got this far, but then I havenít read his latest material, something I must make time to do.


Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 08/08/2020 13:09:55
If you're working with theories that can't handle time correctly, throw them in the bin where they belong.
Einstein’s GR handles black holes just fine since it has no requirement for an absolute ordering of all events. LET does, and since there cannot be such an ordering, it can’t work, so it is forced to deny the existence of these unmappable events.

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Anything that has time run at different rates for different objects breaks by generating event-meshing failures and immediately disqualifies itself from science.
GR is fine then because it doesn’t posit time ‘running’ at all. Neither does LET, but nLET does, and you seem to be pushing a variant of the nLET view.  I’m attacking the preferred foliation premise, not the running-time premise.

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If there’s no singularity, then why can’t you get past it?
Not being able to get past it doesn't mean there are no events further in.
If you deny that those events will ever happen, then it is self-contradictory to assert that there are events further in. I’m pointing out self-contradictions with the view. You’re seemingly confirming these contradictions rather than attempting to resolve them. I’m inside the event horizon relative to some distant Euclidean space, so my existence now is hard evidence that the distant Euclidean space is an invalid choice for the absolute frame. Similarly, his existence invalidates my Euclidean space, so now you have to posit geocentrism and deny the existence of this distant place because we’re special.

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Your whole view of what goes on in a black hole is dictated by the predictions of a broken model in which the event horizon can be crossed.
I explained how an abstract singularity can be crossed since it isn’t physical. This is another strawman assertion. The ‘stuff accumulating on the event horizon’ model was essentially put to rest back in the 60’s. It has contradictions and doesn’t work. I brought up the Rindler thing just to demonstrate the non-physical nature of a mathematical singularity.

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In GTR, if you're suspended by the event horizon, you don't see your old home because "time" stops for you but for someone else falling across the event horizon, it isn't, so they can see out.
You apparently don’t know GTR at all, but I already knew that. You very much can see out since time does not stop for any observer. OK, it stops at the physical singularity, since it is not a location in space but literally a physical end to time. Until that time, an observer can see his old home. I have a link to a stack exchange discussion asking this very question, because some are under the impression that the guy falling in will, due to infinite time dilation, witness the end of the universe, which is shown to be false. There are events on the outside that can never have a causal effect on our guy inside the black hole because they will not reach him before time ends for him. It is events after this point that cannot be objectively ordered with events inside.

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Again that's just nonsense generated by a broken model.
This is all SR, and in flat Euclidean (Minkowski actually) spacetime. Right, you declare ‘broken’ a model you want to be wrong. This is what I mean be ‘sorry to have wasted your time’.

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I got it by analyzing the experiment: not by taking anything from quack sites.
I seriously doubt you have the capability to do that. All your post show invalid strawman rules about how relativity works. No wonder you came to the conclusion that it is some kind of proof. No, I was looking for something more peer reviewed.

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It's a mathematical proof. All observers get the same timing difference. All observers measure the length of the material to be the same in both directions. All competent mathematicians (and high-school maths teachers too) can confirm its validity.
Most mathematicians and high school teachers don't know relativity theory. I want a physicist who knows how to apply the theory correctly, and not just somebody checking things for arithmetic errors.The arithmetic seems trivial in your simulation.
For instance, the analysis of the light ring (Sagnac) on the crank sites always involves cutting the ring up into little local straight pieces and then adding them up as if they were in a straight line. To do it correctly, either one frame must be chosen (makes it easy), or one must rotate the coordinates each time the next segment is added in, which is intense calculus I never see being done because they hope the audience doesn't spot the error.

About the simulation:
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I'll edit a link in here in a few minutes once I've uploaded the program that compares simulations and show GTR generating event-meshing failures alongside the fake version of GTR used in all the simulations that purport to be of GTR but which cheat by smuggling in absolute time...
The program presumes a sort of personal presentism, essentially a real-time moving spotlight for humans only view, with the addition of your assumption of the erasure of any material human that isn't at its own present. I notice the gravity source doesn't have a 'present' (a colored dot), but the observers do. It is a gross misrepresentation of GTR which only talks about worldlines without the moving dot.

This is what I mean by strawman arguments. You fallaciously introduce presentism to 'disprove' a theory that doesn't posit it. There's no concept of a 'meshing error' in a non-presentist view.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 09/08/2020 01:32:12
]Einsteinís GR handles black holes just fine since it has no requirement for an absolute ordering of all events. LET does, and since there cannot be such an ordering, it canít work, so it is forced to deny the existence of these unmappable events.

You're using a model which generates contradictions, and then you rule out a theory that doesn't on the basis that it doesn't reproduce the contradictions of the broken model that you use, and worse, you use LET's failure to break in the same way as your model as evidence that your model must be right! Your model simply can't handle time correctly. It doesn't matter how much brilliance has been built on top of a faulty foundation - so long as it includes the faulty foundation, the whole thing's broken.

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GR is fine then because it doesnít posit time Ďrunningí at all. Neither does LET, but nLET does, and you seem to be pushing a variant of the nLET view.  Iím attacking the preferred foliation premise, not the running-time premise.

If you have no running time, you have no causation, so you're working with a broken model from the start. No apparent effect can have been caused by its apparent cause because no process of any kind ever ran. It's a magic model: not a scientific one.

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If thereís no singularity, then why canít you get past it?
Not being able to get past it doesn't mean there are no events further in.
If you deny that those events will ever happen, then it is self-contradictory to assert that there are events further in.

The frozen stuff in your freezer is starved of events too, but you shouldn't mistake events for time. Time can pass without any events being apparent.

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Iím inside the event horizon relative to some distant Euclidean space, so my existence now is hard evidence that the distant Euclidean space is an invalid choice for the absolute frame.

If you're frozen inside a black ball (which is what a black hole really is), time's still going past for you just as it is for everything outside the ball, but you don't register any of it. You just stay there until you're evaporated away by Hawking radiation trillions of years in the future, and throughout those trillions of years, that's where you are.

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Similarly, his existence invalidates my Euclidean space, so now you have to posit geocentrism and deny the existence of this distant place because weíre special.

Perhaps you're making a mistake in visualising the Euclidean space: it's the same coordinate system for everything inside and outside the black hole. As you descend into a gravity well (without even needing to go into a black hole), your attempts to impose the grid on the things around you goes wrong if you assume that it won't be warped by the speed of light changes with depth, so observers who create what they think are correct grids down there put the lines in the wrong places. In the same way, the correct Euclidean grid lines will look warped to them. The two things must not be conflated.

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Your whole view of what goes on in a black hole is dictated by the predictions of a broken model in which the event horizon can be crossed.
I explained how an abstract singularity can be crossed since it isnít physical. This is another strawman assertion. The Ďstuff accumulating on the event horizoní model was essentially put to rest back in the 60ís. It has contradictions and doesnít work. I brought up the Rindler thing just to demonstrate the non-physical nature of a mathematical singularity.

The idea doesn't appear to have been put to rest at all - it just disagrees with a broken theory which generates contradictions and then uses those contradictions to attack other theories for not generating contradictions too. There is nothing that can be measured from the outside of a black hole that isn't compatible with everything piling up at the event horizon. Everything you think you know about black holes is warped by the broken theory which provides the rules for it - it should have been ruled out right at the start by the event-meshing failures, and the escape route of trying to eliminate the event-meshing failures by eliminating running time forces you into an eternal block with no causation in it which was never created, but just had all that apparent causation written through it by luck alone, while the amount of luck involved in that would be equivalent to entering the lottery every day and winning the jackpot every day for something like the length of time the universe exists to the power of a googolplex. It is not viable science.

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In GTR, if you're suspended by the event horizon, you don't see your old home because "time" stops for you but for someone else falling across the event horizon, it isn't, so they can see out.
You apparently donít know GTR at all, but I already knew that. You very much can see out since time does not stop for any observer.

If you are suspended by the event horizon, your functionality stops so you can't see out. Who is it that's misunderstanding GTR here? Suspend a light clock at the event horizon where the speed of light inwards might be anything from c to 2c (I don't know what it's supposed to be), but outwards the speed of light at that location is zero, so the light clock cannot go on ticking and the person with it cannot be functioning either for the same reason. The light carrying information about events outside the black hole would still be reaching him, but he has no ability to perceive any of it.

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OK, it stops at the physical singularity, since it is not a location in space but literally a physical end to time. Until that time, an observer can see his old home.

Which is viewing from outside the event horizon.

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I have a link to a stack exchange discussion asking this very question, because some are under the impression that the guy falling in will, due to infinite time dilation, witness the end of the universe, which is shown to be false. There are events on the outside that can never have a causal effect on our guy inside the black hole because they will not reach him before time ends for him. It is events after this point that cannot be objectively ordered with events inside.

As he falls in across the event horizon, his inward movement enables light to move outwards relative to him, so his functionality is not frozen in such a case. How long he would be able to go on witnessing external events, I don't know - I haven't explored the predictions of the broken theory far enough to know what would result in terms of how long (in real time rather than proper time) it would take for him to reach the singularity.

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Again that's just nonsense generated by a broken model.
This is all SR, and in flat Euclidean (Minkowski actually) spacetime. Right, you declare Ďbrokení a model you want to be wrong. This is what I mean be Ďsorry to have wasted your timeí.

If it's Spacetime, it's automatically a broken model because it generates event-meshing failures.

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I got it by analyzing the experiment: not by taking anything from quack sites.
I seriously doubt you have the capability to do that. All your post show invalid strawman rules about how relativity works. No wonder you came to the conclusion that it is some kind of proof. No, I was looking for something more peer reviewed.

If all you look at is material endorsed by the clergy, you'll never get out of that mess. I'm not doing anything strawman: I'm testing the foundations of models and finding faults in them which exist not only in the simple cases where they're easiest to see, but in all the complex piles of convoluted junk that people have built on top of them. The event-meshing failures don't magically disappear just because the pile of pants on top of the basic model keeps growing into a mountain.

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Most mathematicians and high school teachers don't know relativity theory.

But they do understand the basic rules of maths which the physicists are breaking.

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I want a physicist who knows how to apply the theory correctly, and not just somebody checking things for arithmetic errors.The arithmetic seems trivial in your simulation.

It is indeed trivial, and yet the physicists get the wrong answer from it because they impose what they want to be true on the experiment and reject what it actually tells them.

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For instance, the analysis of the light ring (Sagnac) on the crank sites always involves cutting the ring up into little local straight pieces and then adding them up as if they were in a straight line. To do it correctly, either one frame must be chosen (makes it easy), or one must rotate the coordinates each time the next segment is added in, which is intense calculus I never see being done because they hope the audience doesn't spot the error.

Well, there's no straight line cutting in my analysis of MGP.

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The program presumes a sort of personal presentism, essentially a real-time moving spotlight for humans only view, with the addition of your assumption of the erasure of any material human that isn't at its own present. I notice the gravity source doesn't have a 'present' (a colored dot), but the observers do. It is a gross misrepresentation of GTR which only talks about worldlines without the moving dot.

The gravity source is at the centre of the biggest dot on the screen. In the left-hand simulation it shouldn't really be shown as a dot on the screen at all as it should already be beyond the top and merely leave a fossilised trace of itself behind if you're using a block universe. I don't know what you mean by the "assumption of the erasure of any material human that isn't at its own present": the trace left behind is the retention of them.

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This is what I mean by strawman arguments. You fallaciously introduce presentism to 'disprove' a theory that doesn't posit it. There's no concept of a 'meshing error' in a non-presentist view.

I have presentism and eternalism both shown at the same time. If you want presentism, focus on the dots. If you want eternalism, focus on the trails. If you want causality to be real in addition to eternalism, then you should focus on the dots as well as a trail because you have to generate your eternal block with a running process to make the causation real, and the block left behind then becomes eternal, but to have an eternal block with no running process to create it in the first place, you're doing magic rather than science.
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 09/08/2020 02:38:33
But they do understand the basic rules of maths which the physicists are breaking.

What rules are being broken?

It is indeed trivial, and yet the physicists get the wrong answer from it because they impose what they want to be true on the experiment and reject what it actually tells them.

Sounds like you are saying that there was an experiment that produced results at odds with relativity. When was that experiment performed? By who? What about the results falsified relativity?
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 09/08/2020 14:48:41
You're using a model which generates contradictions
I am not. Your simulation seems to be using a model which generates contradictions, which I will call General Relativity with Davidís Additions, or GRwDA for short. Yes, I agree that the model is contradictory, but Iím not using that one, nor am I really pushing any model at all in my posts here. Iím merely proposing a contradiction with the idea of a preferred foliation. Youíre the one who decided to drag the second premise of a preferred moment in time.

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If you have no running time, you have no causation
There you go. Thatís a good foot to start on. Demonstrate that statement without a begging definition of causation. You canít do that because you seem incapable of letting go of your biases long enough to consider an alternate view on its own terms. Thatís your handicap. Most of the rest of the physics world has no trouble setting your premises aside, even if they personally believe in them. They can consider an alternate theory on its own grounds and critique it without introducing their beliefs. You on the other hand seem incapable of that, so you probably shouldnít be in the business of disproving views that you donít hold.

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I haven't explored the predictions of the broken theory far enough to know what would result in terms of how long (in real time rather than proper time) it would take for him to reach the singularity.
The theory that you find broken does not posit any concept of Ďreal timeí. Thatís one of your additions, and the one that Iím finding to be self-contradictory for the reasons stated.

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I'm not doing anything strawman
I was quite explicit when point out how youíre doing it. Your biases seem to run so deep that you are perhaps incapable of seeing them even when theyíre explicitly pointed out to you. As I said, thatís your problem, not a problem with a theory that doesnít assume those premises.

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I don't know what you mean by the "assumption of the erasure of any material human that isn't at its own present": the trace left behind is the retention of them.
OK, it seems to be one way. The blue dot gets ahead, and there is no red human yet, who has fallen behind. Nobody gets erased, but if the blue guy waits far enough to the left, heíll suddenly see the red person pop into existence, and simultaneously the red person will see the blue person momentarily Ďdefossilizeí and then blink out, which is sort of Ďhuman erasureí if you ask me.
I slowly lean in to kiss Alice, but my motion puts me slightly in her future, leaving her a short distance in the past. She blinks out of my existence, leaving Alice with only a fossilized trace to mesh with when sheís lonely. Oh wait, I forgot, weíre siblings. Maybe it's for the best then.
That doesnít invoke GR at all.  It is just SRwDA.  I agree that it is trivially falsified by empirical test. The could not exist since any moon would have been left in my past.

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I have presentism and eternalism both shown at the same time.
Both sides have moving dots, so both sides are presentist. Somehow you donít see even that much.  Amazing.

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If you want presentism, focus on the dots. If you want eternalism, focus on the trails.
The trails grow behind the dots. Thatís presentism. Only the final image without the dots is a reasonable depiction of the eternal view, without the preceding Ďsimulationí. Any Ďconstruction phaseí of the block puts time outside of the block, which contradicts time being by definition intrinsic to the block. A B-theory universe cannot be a created thing, but a growing block universe can. The latter is still A-theory, or presentism.

The only difference then (without the dots) is that right side has a preferred foliation (shown in red, and undetectable by any observer) and the left side does not. Thatís the only actual difference between GTR and LET.  Your second addition of the moving dots to both sides makes it GRwDA and nLET respectively, but it is the red numbers that Iím finding contradictory, not the second addition of the dots. If the red numbers are not contradictory, then neither are the dots that require the red numbers. I have no explicit argument against the dots.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 09/08/2020 21:21:43
What rules are being broken?

See post #33: disproofs 1 and 2: mixing measurements from different frames.

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Sounds like you are saying that there was an experiment that produced results at odds with relativity. When was that experiment performed? By who? What about the results falsified relativity?

The details are in post #58: disproof 3.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 09/08/2020 22:02:04
Your simulation seems to be using a model which generates contradictions, which I will call General Relativity with Davidís Additions, or GRwDA for short.

What have I added to GTR? I've simply shown the simplest simulation of it in which there is precisely one kind of time in the model and Newtonian time is kept out. The computer time in the simulation must be the proper time of each object in the simulation: no object's proper time is allowed to run at a different rate from any other object's proper time. In the other simulation (pseudo-GTR), absolute time is brought in to prevent the event-meshing failures, but that breaks the rules of GTR. The challenge is open for people who somehow imagine that GTR's a viable model to show how to simulate it without event-meshing failures and to do it without introducing absolute time. I say it's a mathematically impossible task, but if they're right, they should be able to do it. As it stands, all they have ever produced are the two models shown here, and they delete the first one in a hurry every time they produce it because they think there's a bug in it, but no: that is GTR and it is GTR that contains the bug.

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Youíre the one who decided to drag the second premise of a preferred moment in time.

I did two things. I show how GTR with running time breaks, forcing people cheat in their simulations in order to hide the fatal defect, but I also told you that getting rid of running time fails because it eliminates causation. A model that depends on such extreme amounts of luck that it becomes one of the most unlikely ideas ever imagined while not being technically impossible (i.e. more unlikely than tossing a coin billions of times and always having it land upright on its edge instead of being heads or tails), and that isn't something that science should be backing.

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If you have no running time, you have no causation
There you go. Thatís a good foot to start on. Demonstrate that statement without a begging definition of causation. You canít do that because you seem incapable of letting go of your biases long enough to consider an alternate view on its own terms. Thatís your handicap. Most of the rest of the physics world has no trouble setting your premises aside, even if they personally believe in them. They can consider an alternate theory on its own grounds and critique it without introducing their beliefs. You on the other hand seem incapable of that, so you probably shouldnít be in the business of disproving views that you donít hold.

Pointing out the reality of how bad a broken model is is not a bias. If you never generate the future out of the past, you simply cannot have causation: you have taken away all possibility of any effect being caused by its supposed cause. The action of causation never happens so there is no causation. It's a magic model - not a scientific one.

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The theory that you find broken does not posit any concept of Ďreal timeí. Thatís one of your additions, and the one that Iím finding to be self-contradictory for the reasons stated.

Without real time, all it has is the time of the time dimension which is the proper time of objects, and if that's all you have in the model, you get event-meshing failures which invalidate the model. That is why simulations that purport to be of GTR and don't display event-meshing failures have to cheat by bringing absolute (real) time into them to hide the defect.

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I'm not doing anything strawman
I was quite explicit when point out how youíre doing it.

Respecting mathematics is not a bias. When you insist on using a broken model which has broken mathematically, that's where a bias is in play.

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Your biases seem to run so deep that you are perhaps incapable of seeing them even when theyíre explicitly pointed out to you. As I said, thatís your problem, not a problem with a theory that doesnít assume those premises.

A theory that doesn't conform to the rules of mathematics is rejecting mathematics when it doesn't assume those premises.

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...but if the blue guy waits far enough to the left, heíll suddenly see the red person pop into existence, and simultaneously the red person will see the blue person momentarily Ďdefossilizeí and then blink out, which is sort of Ďhuman erasureí if you ask me.

Well, you've understood that correctly: that's exactly how the universe would be with GTR and no block - you would hardly ever see anything and practically no interactions would occur.

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That doesnít invoke GR at all.  It is just SRwDA.

It is every Spacetime model. It is the establishment's GTR and STR. It is not my model but theirs. But the models they use in simulations are Spacetime+ models where the plus refers to an absolute time which is banned from GTR and STR, but they have to include it in order to hide the brokenness of their models. The only time they use genuine GTR and STR is in eternal static block universes where they eliminate running time, but whenever they do that they destroy causation and replace it with the most ridiculous amount of luck imaginable.

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I have presentism and eternalism both shown at the same time.
Both sides have moving dots, so both sides are presentist. Somehow you donít see even that much.  Amazing.

Eternalism is being shown by the trails left behind: once the dots are off the screen, you're seeing only eternalism left behind. The difference is though that this eternalism is one with a creation: a running process in which causation has a real role. If you want to eliminate the creation process, causation disappears and is replaced by magic - that is not a place where serious science should have to retreat.

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The only difference then (without the dots) is that right side has a preferred foliation (shown in red, and undetectable by any observer) and the left side does not. Thatís the only actual difference between GTR and LET.

LET doesn't have the shortened paths to the future through a non-existent "time" dimension, so there is no dividing by 0.5, and no multiplying by 0.5 to correct the event-meshing failures caused by dividing by 0.5.

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Your second addition of the moving dots to both sides makes it GRwDA and nLET respectively,

Neither model is mine, and neither of them is any version of LET. The model on the left is every Spacetime model, and the model on the right is every model using both Spacetime and absolute time. Your attempt to hide that reality by giving them incorrect names does not alter the fact that the establishment's models are broken beyond repair.

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but it is the red numbers that Iím finding contradictory, not the second addition of the dots. If the red numbers are not contradictory, then neither are the dots that require the red numbers. I have no explicit argument against the dots.

The red numbers come from the proper time of the red twin who is at the same depth in a gravity well as we are. In a more detailed simulation, computer time would be set for anything that's completely outside of all gravity wells, so the red twin's clock would be made to run slow too in the pseudo-GTR simulation, but would tick at the same rate as computer time in the GTR simulation because there is only one kind of time in that model, so they must be the same time.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 10/08/2020 12:08:11
...
I donít see much point in you going over old ground with the SR scenarios, which have been done to death. The bigger question is whether you can take the electrodynamics paper and propose a rigorous alternative which allows accurate transforms and aligns with observations that the laws of electromagnetism are not frame dependent. The big outcome from the electrodynamics paper was the proposal that electric and magnetic fields are not separate, but are different aspects of a single electromagnetic field, can you preserve this or do you have a different proposal. Iím not aware David has got this far, but then I havenít read his latest material, something I must make time to do.


A light clock roundtrip is one of the best proper time clocks.
A light clock roundtrip in an inertial frame will appear time-dilated in any other moving inertial frame.
Is this statement OK?
Does it leave the SR contradictory regarding the determination of the proper time?
Is the twin paradox still an paradox?
What experiment proves the twin paradox not being a logical contradiction?

Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 10/08/2020 16:21:19
...
I donít see much point in you going over old ground with the SR scenarios, which have been done to death. The bigger question is whether you can take the electrodynamics paper and propose a rigorous alternative which allows accurate transforms and aligns with observations that the laws of electromagnetism are not frame dependent. The big outcome from the electrodynamics paper was the proposal that electric and magnetic fields are not separate, but are different aspects of a single electromagnetic field, can you preserve this or do you have a different proposal. Iím not aware David has got this far, but then I havenít read his latest material, something I must make time to do.

A light clock roundtrip is one of the best proper time clocks.
A light clock roundtrip in an inertial frame will appear time-dilated in any other moving inertial frame.
Is this statement OK?
Does it leave the SR contradictory regarding the determination of the proper time?
Is the twin paradox still an paradox?
What experiment proves the twin paradox not being a logical contradiction?
I donít see how this answers my question about Einsteinís electrodynamics paper. Youíve obviously read it, but until you explain your problem with Maxwellís equations, the asymmetry of magnetic and electric fields, and Einsteinís resolution of the problem I donít see we have a common starting point.
What are your proposals for resolving the problem?
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 10/08/2020 22:18:54
...
I donít see much point in you going over old ground with the SR scenarios, which have been done to death. The bigger question is whether you can take the electrodynamics paper and propose a rigorous alternative which allows accurate transforms and aligns with observations that the laws of electromagnetism are not frame dependent. The big outcome from the electrodynamics paper was the proposal that electric and magnetic fields are not separate, but are different aspects of a single electromagnetic field, can you preserve this or do you have a different proposal. Iím not aware David has got this far, but then I havenít read his latest material, something I must make time to do.

A light clock roundtrip is one of the best proper time clocks.
A light clock roundtrip in an inertial frame will appear time-dilated in any other moving inertial frame.
Is this statement OK?
Does it leave the SR contradictory regarding the determination of the proper time?
Is the twin paradox still an paradox?
What experiment proves the twin paradox not being a logical contradiction?
I donít see how this answers my question about Einsteinís electrodynamics paper. Youíve obviously read it, but until you explain your problem with Maxwellís equations, the asymmetry of magnetic and electric fields, and Einsteinís resolution of the problem I donít see we have a common starting point.
What are your proposals for resolving the problem?
Colin,
Let me reach for a book, Hertz did it long time ago,
Jano


(https://i.imgur.com/Zuajxa2.png)

(https://i.imgur.com/oitWfvK.png)

(https://i.imgur.com/QTJjEqo.png)
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 11/08/2020 19:20:55
Perhaps we should focus on this issue of Maxwell's equations to try to spell out exactly what role they have in this. They keep being used as justification of the impossible on a basis that doesn't appear to stack up. They contain a distance term which requires you to program in an assumption of being stationary at the start, thereby leading to that assertion being thrown back at you at the end as "confirmation" of being stationary. I've always said that there must be a more competent set of equations waiting to be found which don't just lazily depend on the phenomenon of relativity to make them work, and this book about Hertz suggests that such a set of more competent equations was found in the 1800s, so I'd like to know more about them.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 12/08/2020 00:28:12
Are the photons of the red 90 degree light beam up comoving with the moving train frame from the platform point of view?

(https://i.imgur.com/JmNaCOK.png)
Title: Re: Is Special Relativity reciprocal?
Post by: Kryptid on 12/08/2020 05:32:37
It's honestly difficult to understand what you are asking. Based on what you were saying in the other thread, I'm guessing that you are trying to say that the light beam will look like it's traveling at a different speed in a frame that is moving relative to the car than in the frame of the car itself. That's not the case. The speed of light is the same in both frames. The consequence of this is that the light beam is seen to hit the far side of the cart at different times in each frame. In the frame where the light beam has to travel further, it takes longer to traverse the distance and thus will take longer to reach its target. That's relativity of simultaneity.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 12/08/2020 05:57:10
It's honestly difficult to understand what you are asking. Based on what you were saying in the other thread, I'm guessing that you are trying to say that the light beam will look like it's traveling at a different speed in a frame that is moving relative to the car than in the frame of the car itself. That's not the case. The speed of light is the same in both frames. The consequence of this is that the light beam is seen to hit the far side of the cart at different times in each frame. In the frame where the light beam has to travel further, it takes longer to traverse the distance and thus will take longer to reach its target. That's relativity of simultaneity.
Correct, the light speed is c in both frames.
The light crosses 1cs' in the train frame in 1s'. The single quote is to reference the moving frame.
The light crosses 2cs in 2s in the platform frame but the light travels under angle in the platform frame.
What is the speed?
The platform view sees the y direction without any contraction therefore it takes 2s to cross 1cs that is equal to 1cs'.
The v_y velocity is c/2 in order to cross 1cs in 2s.
The end result has to be c.
Therefore we have this equation:
c^2 = (c/2)^2 + v^2
v^2 = 0.866c
c^2 = 0.25c^2 + 0.75c^2
c^2 = c^2
The velocity v is comoving/drifting photons with the train car.

When we understand that the time dilation comes from this setup then we can see that v_y = c/gamma is true all the time for any two moving inertial frames.
Point being made by the blue arrow up.
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: hamdani yusuf on 12/08/2020 11:44:08
(https://i.hizliresim.com/TvwQMH.jpg) (https://hizliresim.com/TvwQMH)

In their first meeting astronout A will say to B "Your clock has been lost 2 hours". Also Astronout B will answer: "Your clock has been lost 2 hours too".

In their second meeting A  will say " your clock has been lost 4 hours" B will  answer the same,

....

against causality.
I wonder why no one address this problem? Has anyone encountered similar problem anywhere else?
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 12/08/2020 13:07:00
I wonder why no one address this problem? Has anyone encountered similar problem anywhere else?
There's no problem except for a poorly expressed problem and even more poorly expressed comments below. That's probably why.

(https://i.hizliresim.com/TvwQMH.jpg) (https://hizliresim.com/TvwQMH)
Unclear what is depicted.  It shows a pair of elliptical paths that do not intersect, so it isn't really clear how they're going to meet each other.  Presumably the paths are larger and the gap between them is far smaller than depicted.
The picture indicates that Va=Vb suggesting that the two ships always have the same velocity in which case they cannot ever depart from each other's presence. This contradicts the picture which has the paths diverging, and the ships pointing in opposite directions.
It does not seem that the scenario was taken from any legit physics site.

As long as I'm making fun of the errors in the picture, I might as well point out that it assumes the naive Star-Wars rule that ships in space fly like airplanes, pointing in their direction of motion and banking through the turns (and making noise as they go by). In real physics, space ships point in the direction of acceleration, which implies that they should be pointed up and down respectively, not right and left as depicted.

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In their first meeting astronout A will say to B "Your clock has been lost 2 hours". Also Astronout B will answer: "Your clock has been lost 2 hours too".
I don't know how either astronaut can determine how long the other guy's clock has been lost, but as long as they find it before they meet, does it really matter?

The paths appear symmetrical, so if the clocks were in sync at the first meeting, they'll still be in sync at each meeting. There's not even the appearance of a paradox to resolve.

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...  against causality.
What does this even mean??  How did causality suddenly appear in a discussion otherwise devoid of it? What caused each astronaut to lose his clock for hours? Who can tell?
Title: Re: Is Special Relativity reciprocal?
Post by: hamdani yusuf on 13/08/2020 10:42:04
I wonder why no one address this problem? Has anyone encountered similar problem anywhere else?
There's no problem except for a poorly expressed problem and even more poorly expressed comments below. That's probably why.

(https://i.hizliresim.com/TvwQMH.jpg) (https://hizliresim.com/TvwQMH)
Unclear what is depicted.  It shows a pair of elliptical paths that do not intersect, so it isn't really clear how they're going to meet each other.  Presumably the paths are larger and the gap between them is far smaller than depicted.
The picture indicates that Va=Vb suggesting that the two ships always have the same velocity in which case they cannot ever depart from each other's presence. This contradicts the picture which has the paths diverging, and the ships pointing in opposite directions.
It does not seem that the scenario was taken from any legit physics site.

As long as I'm making fun of the errors in the picture, I might as well point out that it assumes the naive Star-Wars rule that ships in space fly like airplanes, pointing in their direction of motion and banking through the turns (and making noise as they go by). In real physics, space ships point in the direction of acceleration, which implies that they should be pointed up and down respectively, not right and left as depicted.

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In their first meeting astronout A will say to B "Your clock has been lost 2 hours". Also Astronout B will answer: "Your clock has been lost 2 hours too".
I don't know how either astronaut can determine how long the other guy's clock has been lost, but as long as they find it before they meet, does it really matter?

The paths appear symmetrical, so if the clocks were in sync at the first meeting, they'll still be in sync at each meeting. There's not even the appearance of a paradox to resolve.

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...  against causality.
What does this even mean??  How did causality suddenly appear in a discussion otherwise devoid of it? What caused each astronaut to lose his clock for hours? Who can tell?

These are what I see from the picture, by assuming that it's a 3D projection onto 2D screen:
Spaceship A move in a circular trajectory in counter clockwise direction with speed vA.
Spaceship B move in a circular trajectory in clockwise direction with speed vB. B's trajectory is parallel and coaxial with A's.

The acceleration of the ship depends on the position of the thruster. They can use side thrusters, but let's not add unnecessary complexity to the core problem.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 13/08/2020 13:15:01
The paths appear symmetrical, so if the clocks were in sync at the first meeting, they'll still be in sync at each meeting. There's not even the appearance of a paradox to resolve.
These are what I see from the picture, by assuming that it's a 3D projection onto 2D screen:
I thought about that as well,.but they both appeared to be going counterclockwise to me, so I figured the separation between them would never change.
All the problems aside, I left the essence of my answer in my quote above.  There is not even the appearance of a paradox to resolve. Nobody should expect the clocks to get out of sync between passes.
Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 13/08/2020 15:43:01
Colin,
Let me reach for a book, Hertz did it long time ago,
Jano
Ah, I had hoped you might come up with your own idea.
I am familiar with Thomas Phipps papers, somewhere I have some correspondence with him, but I must have archived it when changing system.

If Galilean invariance was the only problem then Phipps could be correct, but we have to understand the history of these competing theories.
Remember, at this time Lorentz had not yet formulated his ideas on electrons so experiments were performed, for example, with charged spheres and so there appeared to be similarities between electrostatics, magnetism and gravity - all viewed as action at a distance.  Not only at a distance,  but according to Newton, instantaneous action at a distance,  Faraday thought this illogical and today we know he was right, but at the time the consensus was instantaneous at a distance. Riemann and Ludwig Lorenz showed, it was possible to modify action at a distance theories to yield finitely propagating electric waves analogous to light waves, and in constructing their theories both Helmholtz and Hertz followed this path.

Maxwellís theory wasnít unique and Helmholtz was trying to determine which of the contending theories was correct. When Hertz was in Karlsruhe he took on Helmholtzí role and showed that a theoretical decision could be made on the basis of predictions for closed currents; and he proved that Maxwellís equations were compatible with the physical assumptions shared by all electrodynamic theories and that the equations of the contending theories (including his own) were not. He concluded that if the choice lay solely between Maxwellís equations and the equations of the other type of theory, then Maxwellís were clearly preferable (but he still didnít endorse Maxwellís physical interpretation of his equations, in particular Maxwellís denial of action at-a-distance). It was not until after Hertz had turned to the production of electric waves in air, after he had published his first experiments on waves, that he at last dropped Helmholtzís action at a distance viewpoint and in 1889 he announced that he could describe his results better from Maxwellís contiguous action viewpoint.

This move away from instantaneous action at a distance is really important and gives us insight into the effect of a charge moving inertially vs an accelerated charge, see https://www.thenakedscientists.com/forum/index.php?topic=77171.msg577138#msg577138
Title: Re: Is Special Relativity reciprocal?
Post by: xersanozgen on 13/08/2020 16:19:17
(https://i.hizliresim.com/TvwQMH.jpg) (https://hizliresim.com/TvwQMH)

In their first meeting astronout A will say to B "Your clock has been lost 2 hours". Also Astronout B will answer: "Your clock has been lost 2 hours too".

In their second meeting A  will say " your clock has been lost 4 hours" B will  answer the same,

....

against causality.

This is Isaac Asimov's mental experiment.
When A is preferred as the reference frame; according to SR, its clock will run at proper tempo and B's clock will fall behind.

If we use B as the reference frame;, this tim,e A's clock must becŲme behind. The clocks are synchronized before starting the movement. Each time in their next meeting, they will perceive the other clock's time   2.x  hours behind its own clock.

The external observer sees both of their clocks equal.

Twins will see the other in the same age. Older, younger are not happened.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 13/08/2020 17:13:53
This is Isaac Asimov's mental experiment.
Reference please.
If Asimov is unfamiliar with relativity physics, I'd think him intelligent enough to consult with somebody who is before publishing something that's wrong.  SR predicts the two clocks will read the same at every meeting.

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When A is preferred as the reference frame, according to SR, its clock will run at proper tempo and B's clock will fall behind.
This is blatantly false. You seem to be attempting to apply an inertial relation to a non-inertial frame.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 13/08/2020 18:18:04
Colin,
Let me reach for a book, Hertz did it long time ago,
Jano
Ah, I had hoped you might come up with your own idea.
I am familiar with Thomas Phipps papers, somewhere I have some correspondence with him, but I must have archived it when changing system.

If Galilean invariance was the only problem then Phipps could be correct, but we have to understand the history of these competing theories.
Remember, at this time Lorentz had not yet formulated his ideas on electrons so experiments were performed, for example, with charged spheres and so there appeared to be similarities between electrostatics, magnetism and gravity - all viewed as action at a distance.  Not only at a distance,  but according to Newton, instantaneous action at a distance,  Faraday thought this illogical and today we know he was right, but at the time the consensus was instantaneous at a distance. Riemann and Ludwig Lorenz showed, it was possible to modify action at a distance theories to yield finitely propagating electric waves analogous to light waves, and in constructing their theories both Helmholtz and Hertz followed this path.

Maxwellís theory wasnít unique and Helmholtz was trying to determine which of the contending theories was correct. When Hertz was in Karlsruhe he took on Helmholtzí role and showed that a theoretical decision could be made on the basis of predictions for closed currents; and he proved that Maxwellís equations were compatible with the physical assumptions shared by all electrodynamic theories and that the equations of the contending theories (including his own) were not. He concluded that if the choice lay solely between Maxwellís equations and the equations of the other type of theory, then Maxwellís were clearly preferable (but he still didnít endorse Maxwellís physical interpretation of his equations, in particular Maxwellís denial of action at-a-distance). It was not until after Hertz had turned to the production of electric waves in air, after he had published his first experiments on waves, that he at last dropped Helmholtzís action at a distance viewpoint and in 1889 he announced that he could describe his results better from Maxwellís contiguous action viewpoint.

This move away from instantaneous action at a distance is really important and gives us insight into the effect of a charge moving inertially vs an accelerated charge, see https://www.thenakedscientists.com/forum/index.php?topic=77171.msg577138#msg577138
If the SR is reciprocal then it leads to delta in coordinate times based on the observers.
This means that different observers do not agree on a proper time of a world line.
If observers do not agree on the world line proper time they do not have time for any equations, partial or full time derivatives.
You twisted the logic, requesting something about some equations but we do not have time for these equations.

Quote
I donít see how this answers my question about Einsteinís electrodynamics paper. Youíve obviously read it, but until you explain your problem with Maxwellís equations, the asymmetry of magnetic and electric fields, and Einsteinís resolution of the problem I donít see we have a common starting point.
What are your proposals for resolving the problem?

What I am saying there is no problem till the proper time is settled.
The Einstein's paper starts with time not the electrodynamics.
I am questioning the time solution first.
Jano

Title: Re: Is Special Relativity reciprocal?
Post by: xersanozgen on 13/08/2020 19:14:22
This is Isaac Asimov's mental experiment.
Reference please.
If Asimov is unfamiliar with relativity physics, I'd think him intelligent enough to consult with somebody who is before publishing something that's wrong.  SR predicts the two clocks will read the same at every meeting.

Quote
When A is preferred as the reference frame, according to SR, its clock will run at proper tempo and B's clock will fall behind.
This is blatantly false. You seem to be attempting to apply an inertial relation to a non-inertial frame.

Asimov  GUIDE TO SCIENCE section: Waves/ Light


In relativity we can choice any one of  actors for reference frame.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 13/08/2020 21:30:25
Asimov  GUIDE TO SCIENCE section: Waves/ Light
I have no copy of that book in front of me. I'd need a link to the page where it says the things you claim it does.
Title: Re: Is Special Relativity reciprocal?
Post by: Colin2B on 15/08/2020 12:34:29
You twisted the logic, requesting something about some equations but we do not have time for these equations.
I donít understand. I havenít twisted any logic. You raised Tomís research, so it was relevant to reply and explain why Hertz rejected his own equations. Iím sorry you donít have time for this as there are some important aspects in there.

If the SR is reciprocal then it leads to delta in coordinate times based on the observers.
This means that different observers do not agree on a proper time of a world line.
If observers do not agree on the world line proper time they do not have time for any equations, partial or full time derivatives.
Galilean relativity is symmetrical/reciprocal, but if you understand it then you wonít get confused; similarly with the Lorentz relativity. Your last sentence looks at it from the wrong point of view.

What I am saying there is no problem till the proper time is settled.
The Einstein's paper starts with time not the electrodynamics.
Remind me of the title of Einsteinís paper, people might be forgiven for thinking it has everything to do with electrodynamics. Thatís where it starts.

Anyway, best of luck with your search.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 15/08/2020 14:55:00
You twisted the logic, requesting something about some equations but we do not have time for these equations.
I donít understand. I havenít twisted any logic. You raised Tomís research, so it was relevant to reply and explain why Hertz rejected his own equations. Iím sorry you donít have time for this as there are some important aspects in there.

If the SR is reciprocal then it leads to delta in coordinate times based on the observers.
This means that different observers do not agree on a proper time of a world line.
If observers do not agree on the world line proper time they do not have time for any equations, partial or full time derivatives.
Galilean relativity is symmetrical/reciprocal, but if you understand it then you wonít get confused; similarly with the Lorentz relativity. Your last sentence looks at it from the wrong point of view.

What I am saying there is no problem till the proper time is settled.
The Einstein's paper starts with time not the electrodynamics.
Remind me of the title of Einsteinís paper, people might be forgiven for thinking it has everything to do with electrodynamics. Thatís where it starts.

Anyway, best of luck with your search.
Colin,
The title is "ON THE ELECTRODYNAMICS OF MOVING BODIES".
The moving bodies is the subject. The subject has an attribute - electrodynamics.
That's how I see it.
It appears Einstein as well because he started with frames, time, distance, ...
There is no electrodynamics if we do not have bodies in existence and motion before.
The simple causality.
Therefore the agreement on time, length, simultaneity, frames, ... has to come prior to electrodynamics.

Having said that, do you remember your discussion with Thomas?
Jano

Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 15/08/2020 20:41:26
Colin,
The following is an interesting analysis.
The acceleration can be simplified.

(https://i.imgur.com/NyGqv4a.png)

One friend pointed out this to me. We can complete an acceleration in some finite time, yes? Let's take the time it takes to go from stationary to whatever fraction of c we are going to use R (in the original rest frame). The minimum time for the journey in that frame is thus 4R. We spend the first R accelerating outwards, the second R decelerating back to zero, the third R accelerating back, and the fourth R decelerating. In this scenario, we need to account for the finite acceleration when calculating the proper time for the traveling twin.

But you could extend the journey. Spend the first R accelerating outwards. Then spend a bunch of time X at constant velocity outbound. Then turn around, and spend a bunch of time X coming back. And then spend the last R decelerating. So the total time would be 4R+2X.

Now suppose X = R. The fact that the acceleration isn't instant still matters, right? Sure.

But what if X = 100R? What if X = 1,000,000R? What if X = 10100 R? At some point, X is sufficiently large compared to R that the total proper time is dominated by what happens during X, and what happens during R becomes an irrelevant perturbation that we don't care about anymore. And that's true no matter what value of R you started with. You can always construct the problem such that you just don't care.

And that's why it's OK to simplify the problem by assuming instantaneous acceleration. It doesn't matter that instantaneous acceleration is impossible. You can construct the problem such that it's an arbitrarily small part of the problem, and therefore you can ignore it.



The above text is a standard accepted point of view by some relativists. Do you agree with that?
Now...


(https://i.imgur.com/mxd1KdL.png)


I assume it is OK to use X/R calculation, right?
The traveling twin accelerates from A and decelerates to B.
Using X/R we are going to ignore the acceleration and deceleration.
But we know it happened and the traveler stopped at B.
They are again in the same reference frame.
What is the distance between them when the traveler stops at B?

If gamma = 2 did the traveler crossed 3.4641cs in 2 seconds?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 15/08/2020 21:38:10
If gamma = 2 did the traveler crossed 3.4641cs in 2 seconds?
You seem to be expressing the speed as proper speed (distance traveled in one frame per unit of time measured in another). This is not limited to light speed, so yes, he moves at a proper speed of 1.7c. 'Decelerating' (as you put it) at the destination is not necessary.
In the same measure, given a fast enough ship, I can visit the far side of the galaxy 60000 light years away before I die.  I'd need a gamma a bit better than 2 to do that.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 16/08/2020 04:46:37
If gamma = 2 did the traveler crossed 3.4641cs in 2 seconds?
You seem to be expressing the speed as proper speed (distance traveled in one frame per unit of time measured in another). This is not limited to light speed, so yes, he moves at a proper speed of 1.7c. 'Decelerating' (as you put it) at the destination is not necessary.
In the same measure, given a fast enough ship, I can visit the far side of the galaxy 60000 light years away before I die.  I'd need a gamma a bit better than 2 to do that.
The traveling twin has to see the stay home twin's 4s of proper time as 8s coordinate time in travelers frame.
That cannot happen if there are 2s of proper time on the traveler's clock. That's the problem,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 16/08/2020 05:24:37
The traveling twin has to see the stay home twin's 4s of proper time as 8s coordinate time in travelers frame.
That cannot happen if there are 2s of proper time on the traveler's clock. That's the problem,
All clocks measure their own proper time, so using the word the way you are is redundant.

So the travelers clock reads 2s at one event, and 8s at a different event. There's no problem with that.

Coordinate time is the ordering of events via any coordinate system of your choice, but you've instead chosen multiple coordinate systems, so your post has no coherent meaning. So pick one.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 16/08/2020 15:44:12
The traveling twin has to see the stay home twin's 4s of proper time as 8s coordinate time in travelers frame.
That cannot happen if there are 2s of proper time on the traveler's clock. That's the problem,
All clocks measure their own proper time, so using the word the way you are is redundant.

So the travelers clock reads 2s at one event, and 8s at a different event. There's no problem with that.

Coordinate time is the ordering of events via any coordinate system of your choice, but you've instead chosen multiple coordinate systems, so your post has no coherent meaning. So pick one.
Halc,
there is a train car with L0=3.4641cs and the platform frame.
Front of the train car is x'=0 and t'=0 and it is align with the platform origin x=0 and t=0.

(https://i.imgur.com/3TyzBkF.png)

So the green B is platform origin and train car front (the train origin) aligned.
There is no motion at the beginning, the motion starts at t=t'=0.
The acceleration, then the deceleration as per the diagram.
It takes 4s of the platform time.
Then everything stops again.
The back of the train car is aligned with the platform origin.
There is a time dilation so the front train clock and the back train clock have both 2s on them, agreed?

How did the platform origin crossed 3.4641cs of the train frame in 2s of the train frame?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 16/08/2020 18:17:43
But what if X = 100R? What if X = 1,000,000R? What if X = 10100 R? At some point, X is sufficiently large compared to R that the total proper time is dominated by what happens during X, and what happens during R becomes an irrelevant perturbation that we don't care about anymore. And that's true no matter what value of R you started with. You can always construct the problem such that you just don't care.

And that's why it's OK to simplify the problem by assuming instantaneous acceleration. It doesn't matter that instantaneous acceleration is impossible. You can construct the problem such that it's an arbitrarily small part of the problem, and therefore you can ignore it.
The scenario below does not reflect this sort of acceleration.  It has no X at all, and is all acceleration both ways.

there is a train car with L0=3.4641cs and the platform frame.
Front of the train car is x'=0 and t'=0 and it is align with the platform origin x=0 and t=0.

(https://i.imgur.com/3TyzBkF.png)

So the green B is platform origin and train car front (the train origin) aligned.
There is no motion at the beginning, the motion starts at t=t'=0.
The acceleration, then the deceleration as per the diagram.
It takes 4s of the platform time.
Then everything stops again.
The back of the train car is aligned with the platform origin.
Sorry, but the diagram doesn't show that.  There are no units labeled on the diagram, but you declare the horizontal lines to be separated by 1 second, then the train car seems only of proper length about 1.25 or so.
A 3.46 cs object cannot be moved its own length and stopped in only 4 platform seconds, at least not with a rigid object as depicted.  A 1.25 cs object can.

Quote
There is a time dilation so the front train clock and the back train clock have both 2s on them, agreed?
No.  The scenario depicted shows something more like 1.25 cs long, and in that scenario, (max speed of about .47c in the picture), clocks at either end will read about 3.75 seconds.

Quote
How did the platform origin crossed 3.4641cs of the train frame in 2s of the train frame?
Because if the train is fast enough in the platform frame, it's clock is dilated as much as you want.  There is no surprise to this.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 17/08/2020 23:43:51
But what if X = 100R? What if X = 1,000,000R? What if X = 10100 R? At some point, X is sufficiently large compared to R that the total proper time is dominated by what happens during X, and what happens during R becomes an irrelevant perturbation that we don't care about anymore. And that's true no matter what value of R you started with. You can always construct the problem such that you just don't care.

And that's why it's OK to simplify the problem by assuming instantaneous acceleration. It doesn't matter that instantaneous acceleration is impossible. You can construct the problem such that it's an arbitrarily small part of the problem, and therefore you can ignore it.
The scenario below does not reflect this sort of acceleration.  It has no X at all, and is all acceleration both ways.

there is a train car with L0=3.4641cs and the platform frame.
Front of the train car is x'=0 and t'=0 and it is align with the platform origin x=0 and t=0.

(https://i.imgur.com/3TyzBkF.png)

So the green B is platform origin and train car front (the train origin) aligned.
There is no motion at the beginning, the motion starts at t=t'=0.
The acceleration, then the deceleration as per the diagram.
It takes 4s of the platform time.
Then everything stops again.
The back of the train car is aligned with the platform origin.
Sorry, but the diagram doesn't show that.  There are no units labeled on the diagram, but you declare the horizontal lines to be separated by 1 second, then the train car seems only of proper length about 1.25 or so.
A 3.46 cs object cannot be moved its own length and stopped in only 4 platform seconds, at least not with a rigid object as depicted.  A 1.25 cs object can.

Quote
There is a time dilation so the front train clock and the back train clock have both 2s on them, agreed?
No.  The scenario depicted shows something more like 1.25 cs long, and in that scenario, (max speed of about .47c in the picture), clocks at either end will read about 3.75 seconds.

Quote
How did the platform origin crossed 3.4641cs of the train frame in 2s of the train frame?
Because if the train is fast enough in the platform frame, it's clock is dilated as much as you want.  There is no surprise to this.


Yes, there is no X in the yellow diagram. It tries to show that after traveling to the right both twins are in the same frame, that's all.
If we have L0=3.4641cs train car accelerating/decelerating to the right for 4s of the stay home platform frame then these are the diagrams:

(https://i.imgur.com/LJqTlX6.png)


Where are the B and C events on the right diagram?
B is on ct' axis at t'=2s'. Do you agree?
Where is C?
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 18/08/2020 03:53:22
Yes, there is no X in the yellow diagram. It tries to show that after traveling to the right both twins are in the same frame, that's all.
The other picture shows far more than that.

Quote
If we have L0=3.4641cs train car accelerating/decelerating to the right for 4s of the stay home platform frame then these are the diagrams:

(https://i.imgur.com/LJqTlX6.png)
Those diagrams do not show that at all.  It shows inertial motion without any acceleration, and it does even that incorrectly since no length contraction is depicted, so you get self-contradictions.
I mean, look at the green platform line. You have it moving at -1.73c, which is impossible.

Quote
Where are the B and C events on the right diagram?
You see, a contradiction.  The right diagram does not depict the same scenario as the left, so there is not necessarily a B or C in it.

Quote
B is on ct' axis at t'=2s'. Do you agree?
Sort of.  It's a different (smaller) train car, so not clear if there's any correspondence between the diagrams at all. If we remove the trains and platforms altogether and just consider the two coordinate systems, then yes.

Quote
Where is C?
A is the origin of both frames. B is on the t' axis at 2' seconds and C is 4s on the t axis, which is coordinate t'=8, x'=-6.928 which is immediately below the "ct" label at the top of the chart.
Left chart shows the left end of a train present at C, and the right chart does not, so the two charts do not correspond to the same scenario.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 18/08/2020 04:20:04
Yes, there is no X in the yellow diagram. It tries to show that after traveling to the right both twins are in the same frame, that's all.
The other picture shows far more than that.

Quote
If we have L0=3.4641cs train car accelerating/decelerating to the right for 4s of the stay home platform frame then these are the diagrams:

(https://i.imgur.com/LJqTlX6.png)
Those diagrams do not show that at all.  It shows inertial motion without any acceleration, and it does even that incorrectly since no length contraction is depicted, so you get self-contradictions.
I mean, look at the green platform line. You have it moving at -1.73c, which is impossible.

Quote
Where are the B and C events on the right diagram?
You see, a contradiction.  The right diagram does not depict the same scenario as the left, so there is not necessarily a B or C in it.

Quote
B is on ct' axis at t'=2s'. Do you agree?
Sort of.  It's a different (smaller) train car, so not clear if there's any correspondence between the diagrams at all. If we remove the trains and platforms altogether and just consider the two coordinate systems, then yes.

Quote
Where is C?
A is the origin of both frames. B is on the t' axis at 2' seconds and C is 4s on the t axis, which is coordinate t'=8, x'=-6.928 which is immediately below the "ct" label at the top of the chart.
Left chart shows the left end of a train present at C, and the right chart does not, so the two charts do not correspond to the same scenario.

Halc,
they do correspond to the same scenario.
This is a better diagram:

(https://i.imgur.com/6Xw9DFg.png)


The C event is the problem one.
It shows that the platform ruler crossed the 3.4641cs distance in 2s'.
That's what happened.
How else can we show it?





Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 18/08/2020 06:41:09
Now everything is moving faster than light on the right picture.  Fail
You're also trying to add acceleration (of the platform no less) to it, in which case you need to make it look like the yellow diagram which shows acceleration.  If you want to add a long X time where it is inertial, then fine, but you'll need a significantly larger graph.

This recent thing depicts inertial motion, and needs to stay that way.
Quote
How else can we show it?

* inertial.jpg (17.12 kB . 201x182 - viewed 927 times)

Actually read my prior post, and not just one sentence of it.
Title: Re: Is Special Relativity reciprocal?
Post by: puppypower on 18/08/2020 11:51:58
Special relativity has three variables which are mass, distance and time. If we only use two variables, such as only time and distance, reference can and will appear relative. Mass allow us to feel inertia such as the wind through our hair to confirm motion. It also allows us to do an energy balance since motion will imply velocity and velocity times mass, which gives us momentum and kinetic energy, as well as action and reaction affects. Pretending in only space and time will not do this.

Say one reference mass is m and the other reference mass is 2m and we ignore the mass, then it will appear to be relative motion, If we include the mass each scenario in the relative motion illusion will create a different energy balance due to different mass. Then we will realize that that relative motion violates energy conservation, unless you assume both have the exact same mass. This s why we use the twin paradox. This allows a reactive reference magic trick based on hiding the mass. Instead of twins, use father and son, with the father having twice the mass of the son then you see something is wrong.

Where the problem originally stemmed was in astral physics and astronomy There we depend on  light and energy to observe motion in the universe. Light has only frequency and wavelength, but not mass. Therefore we can only use two of the three SR variables by default. Einstein warned that this situation will create relative reference magic tricks. He was not stating that relative reference was a truth of nature, but giving us a warning that two of three SR variables will create a spatial illusion A spatial illusion will make 2-D appear 3-D or flat 2-D logic will appear like a ball; universal truth,  due to the shadowing and highlights (denial and partial data). .

Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 18/08/2020 14:22:41
Now everything is moving faster than light on the right picture.  Fail
You're also trying to add acceleration (of the platform no less) to it, in which case you need to make it look like the yellow diagram which shows acceleration.  If you want to add a long X time where it is inertial, then fine, but you'll need a significantly larger graph.

This recent thing depicts inertial motion, and needs to stay that way.
Quote
How else can we show it?

* inertial.jpg (17.12 kB . 201x182 - viewed 927 times)

Actually read my prior post, and not just one sentence of it.

Halc,
there is not relative motion after 2s'.
How is it captured in your diagram?
Why there is ct still under angle?
Jano

Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 18/08/2020 14:34:31
Special relativity has three variables which are mass, distance and time. If we only use two variables, such as only time and distance, reference can and will appear relative. Mass allow us to feel inertia such as the wind through our hair to confirm motion. It also allows us to do an energy balance since motion will imply velocity and velocity times mass, which gives us momentum and kinetic energy, as well as action and reaction affects. Pretending in only space and time will not do this.

Say one reference mass is m and the other reference mass is 2m and we ignore the mass, then it will appear to be relative motion, If we include the mass each scenario in the relative motion illusion will create a different energy balance due to different mass. Then we will realize that that relative motion violates energy conservation, unless you assume both have the exact same mass. This s why we use the twin paradox. This allows a reactive reference magic trick based on hiding the mass. Instead of twins, use father and son, with the father having twice the mass of the son then you see something is wrong.

Where the problem originally stemmed was in astral physics and astronomy There we depend on  light and energy to observe motion in the universe. Light has only frequency and wavelength, but not mass. Therefore we can only use two of the three SR variables by default. Einstein warned that this situation will create relative reference magic tricks. He was not stating that relative reference was a truth of nature, but giving us a warning that two of three SR variables will create a spatial illusion A spatial illusion will make 2-D appear 3-D or flat 2-D logic will appear like a ball; universal truth,  due to the shadowing and highlights (denial and partial data). .


Physical objects have mass and energy centroids (centers).
The centroids are frame dependent.
This is very tricky and puzzling,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 18/08/2020 16:24:08
there is not relative motion after 2s'.
There is in my picture.  It is a picture of inertial motion, as was yours in post 95.  If you want acceleration, then you need to draw that, which is depicted in the post 93 drawing.  If you want to coast for 2 seconds between acceleration and deceleration time, then you need to add that to the post 93 drawing.
If you want to draw the acceleration scenario from the x' frame, then you need to add some acceleration at each end of the two seconds.  Only a point object can be entirely accelerated in negligible time.  A long object necessarily takes time, as your post 93 picture shows.  Notice it takes the left side 1 unit of time (as measured in the frame depicted) to accelerate the left end, but 3 units to stop it.  The right side takes 3 to accelerate and 1 to stop.

Quote
Why there is ct still under angle?
The drawing is done relative to the ct' frame, just like the right side drawing of your post 95. ct is always at that angle in that inertial frame. That much you got correct.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 22/08/2020 17:12:28
Halc,
here is the reciprocity of the Special Relativity:

(https://i.imgur.com/YaEiYmb.png)

Therefore this cannot happen and as you said: "You have it moving at -1.73c, which is impossible."

(https://i.imgur.com/6Xw9DFg.png)


... but this is the correct diagram:


(https://i.imgur.com/iBWTS1v.png)


This tells us that the traveling twin's proper time is 4s' to cross the 3.4641cs' distance.
The conclusion is that when the traveling twin accelerates and then decelerates the proper time is going to be the same as the stay home twin.
Jano

Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 22/08/2020 23:57:24
Halc,
here is the reciprocity of the Special Relativity
First picture has no text, so I have no idea what either is trying to depict.
There's an object moving to the right in the first frame, but nothing stationary.  There's a (presumably) different object moving to the left in the second frame. Neither object is in both pictures.  Absent any text to go with it, it is a pictorial equivalent of word salad.

Quote
Therefore this cannot happen and as you said: "You have it moving at -1.73c, which is impossible."
Yes, your middle-right picture has the green thing moving distance 3.4cs in 2 seconds, which is far faster than light (the red dashed line).


Quote
... but this is the correct diagram
It has at least half a dozen contradictions, so it cannot be correct. Why is the train accelerating in the left picture but not in the right, and the platform accelerating in the right picture but not in the left? That's the main contradiction.

Just to name one more, imagine a light beam sent from the rear of the black train (unlabeled event left of event A in left picture).  After 4s, this light has barely moved up the train, still very close to event C. That much is fine, but it contradicts the drawing on the right. In that drawing, the event is labeled '0' for some reason. A light beam after 4s' will pass to the right of event B, not well to the left of event B as depicted in the left picture.


Quote
This tells us that the traveling twin's proper time is 4s' to cross the 3.4641cs' distance.
Wrong.  In the traveling twin frame, he is stationary, so he travels zero distance in 4s' time. Your picture shows this, even if it is inconsistent. The black 'train' is unmoved for 4 seconds in the x'/ct' frame.

What the pictures actually tell me is that you seem to have no intention of listening to anyone pointing out where your pictures cannot be correct. So why should I bother? Post whatever nonsense you want. This is New Theories section. You've been falsified. Maybe it should all be in That-Can't-Be-True.

Quote
The conclusion is that when the traveling twin accelerates and then decelerates the proper time is going to be the same as the stay home twin.
Until you draw something lacking in self-contradictions, you've shown only pretty drawings.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 25/08/2020 20:19:16
I have just thought of a way to break one key part of relativity by narrowing the absolute frame down to a small range, and this is possible because the big bang is a universal starting gun.

Suppose most of the material in the universe is close to being at rest rather than moving at relativistic speed. In such a situation, if you were to travel for billions of years at relativistic speed, you could measure the age of the stars and galaxies that youíre passing and you would determine that theyíre aging faster than you, which reveals that you are the one moving at relativistic speed. However, if all of that material is actually moving at relativistic speed and you are the one who is close to being at rest, you will make the same kind of measurements and see that you are the one whoís aged much faster than the rest of the content of the universe.

We canít do that experiment today unless we happen to find some ancient star passing us at relativistic speed which can in some way tell us how much time it thinks itís measured since the early days of the universe, but we could in principle do it over billions of years in the future and add this to the experiments that have already revealed that LET is right and that STR is wrong, although it would also take a long time to relay the results of the experiment back home.

Note that if we had multiple ancient stars flung out of ancient galaxies passing us in different directions at high relativistic speed, it would be impossible for them all to have aged the same amount. With only one such star, we could be moving at the same speed as it in the opposite direction, but with many such stars moving in different directions, that wouldnít be possible for each of them in relation to us: some of them would have to have very different measurements of how long they have existed since the big bang (and when they came into being) because it would violate the rules of relativity for them not to show up such differences, and this would necessarily help us to pin down the identity of the absolute frame to a narrow range.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 26/08/2020 18:17:14
I have just thought of a way to break one key part of relativity by narrowing the absolute frame down to a small range, and this is possible because the big bang is a universal starting gun.
If it breaks relativity, then it breaks whatever you're pushing because you claim it makes no different predictions.

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Suppose most of the material in the universe is close to being at rest rather than moving at relativistic speed.
You're describing a different universe then, one with no recession of distant galaxies.

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In such a situation, if you were to travel for billions of years at relativistic speed, you could measure the age of the stars and galaxies that youíre passing and you would determine that theyíre aging faster than you, which reveals that you are the one moving at relativistic speed.
Let's see, you have a universe full of clocks that are mostly A) relatively stationary relative to inertial frame X, and B) in sync only in frame X.  That would indeed suggest a preferred frame, one in which there was no big bang, but rather a static-sized universe in which time started everywhere at once.  All very nice, but it's not our universe.
It would not break SR because SR does not forbid such a situation, except perhaps the strawman SR that you invoke.  It would break GR, because GR describes our universe, not this thing you're describing. There would definitely be empirical differences.

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We canít do that experiment today unless we happen to find some ancient star passing us at relativistic speed which can in some way tell us how much time it thinks itís measured since the early days of the universe
OK, I'll bite.  Suppose there's a galaxy somewhere that does not have a velocity relative to its surroundings.  At a time the universe appears about 1.7 billion years old to an observer there, they fire a clock in the direction of us at .999999c or however fast you like. The local universe will appear 12 billion years older (13.7 BY) when it gets here.
It seems that you claim a discrepancy between your view and relativity.  SR has nothing to say about it since SR is not a model of the universe.  So my question is, what is the empirical difference?  So some interesting questions:
1) What is the proper distance between the event of that clock being fired and the material that would eventually become our solar system?  Assume our solar system is similarly relatively stationary relative to its surroundings.
2) How fast does this clock move as it passes by Earth?
3) What does the clock read?  Assume it was zeroed when fired.  It's moving fast, so probably less than 12 BY.

If the theories produce different answers, I need both. If they don't, then what does the experiment demonstrate?
Personally I don't think you're up to that, and thus are free to believe whatever you want in ignorance.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 26/08/2020 18:52:10
The thread title is about the SR reciprocity.
Can we settle that the reciprocity of the SR is a fact?
It follows from this...

(https://i.imgur.com/JmNaCOK.png)


... and this...


(https://i.imgur.com/YaEiYmb.png)


Assuming this is the case the discussion turned what it means for the twin paradox.
So I just want to clarify that we agree on the fact that the SR is reciprocal.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 26/08/2020 20:28:42
If it breaks relativity, then it breaks whatever you're pushing because you claim it makes no different predictions.

No. LET is fully compatible with relativity breaking in this way - it simply reduces the range of the phenomenon of relativity by providing a means to pin down the absolute frame.

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You're describing a different universe then, one with no recession of distant galaxies.

Wrong again. The expansion of the universe simply means that the absolute frame at one location isn't the same as the absolute frame at another location. That doesn't make any dent in this proof. I explained the complications of defining the absolute frame in an expanding universe before where the expansion reveals that the absolute frames which are different for different locations are merely pseudo-absolute frames while the real absolute frame within which the universe is expanding need not correspond to any frame in the universe.

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Let's see, you have a universe full of clocks that are mostly A) relatively stationary relative to inertial frame X, and B) in sync only in frame X.  That would indeed suggest a preferred frame, one in which there was no big bang, but rather a static-sized universe in which time started everywhere at once.  All very nice, but it's not our universe.

No. I'm describing a universe that expands out from a big bang. If something moves through the expanding fabric, it ages more slowly than something that merely goes where the fabric takes it.

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It would not break SR because SR does not forbid such a situation, except perhaps the strawman SR that you invoke.  It would break GR, because GR describes our universe, not this thing you're describing. There would definitely be empirical differences.

STR is so broken that it doesn't take much to invalidate it, as I've shown before, but you just trust in the authority of apes over the authority of mathematics and reject every proof that goes against your beliefs, just like a follower of any other religion. This latest proof destroys STR in a new way, and breaks relativity too as a bonus. GTR is also horribly broken, but this new proof only adds to that destruction indirectly in that anything that damages STR damages GTR too.

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Suppose there's a galaxy somewhere that does not have a velocity relative to its surroundings.  At a time the universe appears about 1.7 billion years old to an observer there, they fire a clock in the direction of us at .999999c or however fast you like. The local universe will appear 12 billion years older (13.7 BY) when it gets here.

Yes, and that's the part that doesn't directly reveal anything until you think through the other case where the galaxy is moving at 0.999999c and sends the clock out at a speed that turns out to be zero. Instead of that clock having its functionality nearly frozen, it ticks inordinately faster than the clocks in all the galaxies which are moving in the same direction through space at 0.999999c.

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It seems that you claim a discrepancy between your view and relativity.  SR has nothing to say about it since SR is not a model of the universe.

When that clock arrives here in the second case, if finds a universe that looks much younger than in the first case, so this is a way to measure absolute speed through the space fabric.

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So my question is, what is the empirical difference?

The difference is that LET survives the breaking of relativity as it doesn't depend on it lasting, whereas STR depends totally on this breakage not occurring.

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1) What is the proper distance between the event of that clock being fired and the material that would eventually become our solar system?  Assume our solar system is similarly relatively stationary relative to its surroundings.
2) How fast does this clock move as it passes by Earth?
3) What does the clock read?  Assume it was zeroed when fired.  It's moving fast, so probably less than 12 BY.

You can fit your own numbers to it. All you need to do is go where the thought experiment takes you. I've written a new version of it which I'll post after this post so as not to have all this bloat as an unnecessary header on it.

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If the theories produce different answers, I need both. If they don't, then what does the experiment demonstrate?

STR contradicts itself, so it can tell every girl that it's deeply in love with her and that it has no interest in any other, and they're all stupid enough to believe it. The key point with this proof though is that it breaks relativity itself, and it does it by applying LET and/or STR to a thought experiment that could be carried out in this universe, though with our starting point for it being so late it might take a trillion years to get an answer. Fortunately though, we can prove it in principle without having to do the actual experiment.

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Personally I don't think you're up to that, and thus are free to believe whatever you want in ignorance.

Lovely. You're the one who might not be up to this stuff, but you're certainly closer to having that ability than most, so I wouldn't be greatly surprised if you're one of the first to make the transition away from Einstein's pile of pants. The ignorance is all yours here though - you've had proof after proof set in front of your eyes and you're blind to them, but that's the norm everywhere when trying to deprogram people who've been so viciously brainwashed by the establishment.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 26/08/2020 20:30:01
Disproof 7

This is a special disproof because it not only destroys STR (like the other disproofs), but it also breaks relativity by allowing the absolute frame to be identified if the right evidence is available, and it breaks it even if all we have to work with is this thought experiment. It all depends on the big bang serving as the start for a set of timers.

Imagine that a particular type of galaxy forms first and that there's a shortage of heavy elements in them because there haven't been any supernovae yet to create them. We can age galaxies and their stars by studying their composition. Now, suppose that all the galaxies are approximately at rest in the local absolute frame (local, because it varies from place to place in an expanding universe). In this case, which we'll call case 1, they will all age quickly. However, if they're all moving through the absolute frame instead at high relativistic speed in the same direction, they will all age slowly, but no one measuring them will be able to tell the difference. We'll call this case 2. Both cases look identical to the inhabitants at this point.

What happens though if there are some stars being flung out of galaxies at high relativistic speeds relative to them. If such stars exist, we could theoretically investigate them as they pass us and determine their age by studying their composition, and we can compare that with our own. If these stars show less aging than our galaxy's stars, then the visitors have been moving faster through the absolute frame. If they show more aging than our galaxy's stars though, then it must be our galaxy that's moving faster through space. We thus have a way of pinning down the absolute frame, or at least of narrowing down the range in which it sits.

This is like a special twins paradox, but with triplets or quads, or any bigger number: multuplets, might be the word (from multi, so pronounced mull-TYOO-plits). The multuplets are effectively separated at the big bang, although they don't actually come into existence straight away, but they do come into being at the same time because their galaxies are all moving at the same speed through space. Many of the the multuplets' stars wander too close to violently exploding objects and get jetted out of their galaxies at high relativistic speeds. Some of them come our way from their original galaxies and we an ask them their age as they fly by. If we are relatively stationary, they will all be younger than the multuplets that live here (the stay-at-home twins), and as they pass by, this counts as a reunion of "twins" (technically pairs of multuplets). They're moving faster relative to us, so STR tells us that these travelling "twins" (the ones who have accelerated) will have aged less. LET also predicts the same for case 1 where we are relatively stationary. However, in case 2 where all the galaxies are moving along through the absolute frame in the same general direction at high relativistic speed, some of the travelling twins will be at rest in that frame while they travel to us and so they will have aged more than us. On discovering that some of the travelling "twins" are much older than our multuplets, the establishment may wish to claim that we must have accelerated more than they did right at the time of the big bang, but no: the travelling "twins" would all have had to do that same acceleration too, so they've certainly accelerated more than we have once you add their jetting acceleration to that. Here we have a special case where we can tell that one specific "twin" is closer to being at rest in the absolute frame of the space fabric than us, and than the other travelling multuplets who are moving in other directions. Case 2 would show this up clearly.

If we happen to find a case 1 result, which is the most likely result, all the travelling twins who pass each other will have aged the same amount, so we don't have a result there that directly pins down (or narrows down) the identity of the absolute frame. However, these multuplets are a clever bunch. They anticipated this problem during the early times of the universe and sent out clocks at relativistic speeds relative to them in all directions, and all these clocks record the history of when and how this was done. So it turns out that we can identify sets of multuplets who are all moving in the same direction at the same speed and also identify the clocks sent out by them in specific directions at specific speeds. Set A of multuplets are all moving at relativistic speed in the direction we call north, while we are stationary (because this is case 1). Set A's clocks are clocks that Set A sent out at relativistic speed in all directions. Members of set A will pass clocks from their own set from time to time and these two sets of objects now serve as a case 2 equivalent where set A members stand in for galaxies and the clocks they've sent out serve as the stars shot out of those galaxies at relativisic speeds. When they ask those clocks their age, some of them will be older than set A members, and some will be younger than them, and the ones which are older than them must be closer to being at rest in the absolute frame. When we look at these clocks ourselves, we see some of them pass us at ridiculously high relativistic speeds much higher than those of the multuplets, but others aren't moving fast relative to us at all, and when we ask them their ages, the ones moving slowest relative to us are the oldest ones, so to us we see a result compatible with STR, but when we take in the measurements made by set A's multuplets, we get a different story from them: they can see what we can't tell directly without their help: they can pin down the absolute frame (at least to a narrow range).

So, it isn't just STR that breaks again, but relativity itself has broken. LET still describes the phenomenon of relativity correctly and predicts all the happenings of this thought experiment, but we find that the phenomenon of relativity itself has a chink in it and that we can crack it wide open.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 26/08/2020 22:26:36
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You're describing a different universe then, one with no recession of distant galaxies.
Wrong again. The expansion of the universe simply means that the absolute frame at one location isn't the same as the absolute frame at another location.
OK, you're talking about the comoving frame, or the FLRW model, which is pretty much the accepted model. That wasn't clear. Most of your posts tend to think on an inertial mindset, so I assumed such a reference when you said everything was nearly stationary.

OK, I know the model.  Earth's 'proper' speed regularly ranges from about 0.13%c to over twice that, with its current speed near the low range of that. Few large objects are seen with proper speeds greater than say 0.5%c. A star isn't a large object. S2 for instance gets up to ~1.6%c, but that's relative to Sgr-A, not a proper speed.

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STR is so broken that it doesn't take much to invalidate it
Nonsense. It isn't a model of the universe is all. It's a model of local spacetime without gravity in consideration. Given those conditions, it cannot be falsified.

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Suppose there's a galaxy somewhere that does not have a velocity relative to its surroundings.  At a time the universe appears about 1.7 billion years old to an observer there, they fire a clock in the direction of us at .999999c or however fast you like. The local universe will appear 12 billion years older (13.7 BY) when it gets here.
Yes, and that's the part that doesn't directly reveal anything until you think through the other case where the galaxy is moving at 0.999999c and sends the clock out at a speed that turns out to be zero.
Now now, the condition is that the galaxy is stationary as you defined above. I'm accepting that. I'm asking you to answer the three questions. A 4th question could be the recession speed of that galaxy, but that is time dependent in the FLRW model, so it isn't receding as fast now as it was 12 billion years ago.

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Instead of that clock having its functionality nearly frozen, it ticks inordinately faster than the clocks in all the galaxies which are moving in the same direction through space at 0.999999c.
Computations please.  You make it sound like some other theory predicts different numbers.

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When that clock arrives here in the second case, if finds a universe that looks much younger than in the first case, so this is a way to measure absolute speed through the space fabric.
Numbers please, or this is all just your fantasy.

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So my question is, what is the empirical difference?
The difference is that LET survives the breaking of relativity as it doesn't depend on it lasting, whereas STR depends totally on this breakage not occurring.
That's a paper difference, not an empirical one. Boo...

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1) What is the proper distance between the event of that clock being fired and the material that would eventually become our solar system?  Assume our solar system is similarly relatively stationary relative to its surroundings.
2) How fast does this clock move as it passes by Earth?
3) What does the clock read?  Assume it was zeroed when fired.  It's moving fast, so probably less than 12 BY.
You can fit your own numbers to it. All you need to do is go where the thought experiment takes you. I've written a new version of it which I'll post after this post so as not to have all this bloat as an unnecessary header on it.
As I thought. You have no numbers. I thought my questions were reasonable. You have no evidence at all if you can't provide simple numbers.
It's not easy to just find on the web since almost all the sites talk about light getting here from the distant galaxy, and light always moves at c even through frame changes. So finding an article on a ballistic object like we're proposing here I thought was an interesting case.

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STR contradicts itself
STR is mute on this experiment since it is not a local experiment. So you need to reach for GR, which does indeed have an answer, even it it isn't a trivial thing to compute.

Quote from: Halc
Personally I don't think you're up to that, and thus are free to believe whatever you want in ignorance.
I was right though. No numbers. You're not up to it.
There's plenty beyond my skills as well, but I don't go asserting conclusions and contradictions then, and if I do see a contradiction (and I do quite often), I assume it is me making the mistake, and not that I've somehow found something that far smarter people cannot.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 26/08/2020 23:27:42
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STR is so broken that it doesn't take much to invalidate it
Nonsense. It isn't a model of the universe is all. It's a model of local spacetime without gravity in consideration. Given those conditions, it cannot be falsified.

It invalidates itself in multiple ways. You simply reject proofs in the same way that religious people reject proofs that their God cannot meet the impossible qualifications required of him.

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Yes, and that's the part that doesn't directly reveal anything until you think through the other case where the galaxy is moving at 0.999999c and sends the clock out at a speed that turns out to be zero.
Now now, the condition is that the galaxy is stationary as you defined above.

There are two cases, and you're homing in on the one that doesn't directly show up anything. You have to look at the other case that you see what matters here.

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Computations please.  You make it sound like some other theory predicts different numbers.

You should be able to fit your own numbers to it without needing help from me. If someone gives you an equation like a = b + c, you don't need to demand numbers to go with it as you can supply any values of your own to it. You are effectively being offered all possible numbers that fit the equation.

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When that clock arrives here in the second case, if finds a universe that looks much younger than in the first case, so this is a way to measure absolute speed through the space fabric.
Numbers please, or this is all just your fantasy.

I gave you numbers. "Much younger" contains a number. "Ages more" contains a number. "Ages less" contains a number. These numbers don't have specific values, but they have ranges which don't overlap in any specific case here. You can pick any numbers you like which follow the rules in the description and they will match up to the stated claims. It's so trivially simple that you should be embarrassed about asking for specific numbers, just as you would be if you had to ask for numbers to understand a = b + c.

In case 1, the speed of the galaxies is approximately zero, so you can test that by using 0, or 0.1c if you like. All the multuplets are created at the same time as each other. In case 2, the speed of the galaxies is any high relativistic speed, so you can make that anything from 0.99999999c or 0.9c. You could make the slow speed 0.49c and the high speed 5.1c if you like too, and it would still work, but the difference would be smaller, so it makes sense to go for a big difference when you assign numbers to this. I don't know why you want me to choose specific numbers when I'm giving you a free choice. In case 2, all the multuplets are created at the same time again, but it's a much later same time than in case 1 because the high speed of movement delays their creation considerably. And "considerably" is again a number, so stop asserting that I'm not giving you numbers. You need to learn what a number is, and I don't need to do your work for you when you pick values: you should be able to crunch them easily enough to see that they fit my claims every time, and you shouldn't even need to do any calculations to know that that will happen. Here's why:-

Case 1: the galaxies are stationary. The multuplets ejected from them at 0.999...c practically stop aging as they travel through space, so when multuplets pass us, we see them in an ancient state.

Case 2: the galaxies are moving at 0.999...c. Some of he multuplets ejected from them are moving through space at zero, and when we run across them we can see that we are the ones in an ancient state compared to them.

You don't need me to calculate their ages and give you precise values for that to know that the above statements are correct, so you can do all that superfulous work for yourself. Go ahead and see if you can find any values using specific speeds that contradict the above statements which cover all possible speeds that you want to try. Asking me to do that for you is not something anyone serious in a discussion like this should be doing. There is no set of valid values (conforming to the set conditions) which breaks the claims of the above statements, and that should be obvious right from the start.

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So my question is, what is the empirical difference?
The difference is that LET survives the breaking of relativity as it doesn't depend on it lasting, whereas STR depends totally on this breakage not occurring.
That's a paper difference, not an empirical one. Boo...

One theory survives relativity breaking and the other doesn't. That is the crucial difference. Theories are things that exist on paper, and they can be destroyed on paper.

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You have no numbers. I thought my questions were reasonable. You have no evidence at all if you can't provide simple numbers.

On the contrary, I have all the numbers and so do you. You can crunch as many pointless specific values as you like, but they will not overturn what has already been proved with my open numbers which cover all valid values (where validity requires a lower value (the speed of the thing moving nearer to 0) to be lower than a higher value (for the thing moving nearer to c)).

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STR contradicts itself
STR is mute on this experiment since it is not a local experiment. So you need to reach for GR, which does indeed have an answer, even it it isn't a trivial thing to compute.

STR is not exempt from being tied up in this experiment. It makes claims which are manifestly disproved by this. The symmetry is broken so badly that relativity itself breaks on it.

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Quote from: Halc
Personally I don't think you're up to that, and thus are free to believe whatever you want in ignorance.
I was right though. No numbers. You're not up to it.

The failure here was all yours: I supplied all the numbers you need and you failed to recognise it.

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There's plenty beyond my skills as well, but I don't go asserting conclusions and contradictions then, and if I do see a contradiction (and I do quite often), I assume it is me making the mistake, and not that I've somehow found something that far smarter people cannot.

Your whole approach fails because you imagine that you're dealing with smarter people when you read establishment nonsense, and you fall in line behind it instead of trusting your own mind. You don't make progress by just trusting authorities to have done the homework which they failed to do.

Case 1: galaxy speeds = 0. Travelling multuplets' speed, a fraction under c. Age of all travelling multuplets is much younger than the stay-at-home multuplets in the galaxies they're passing. Why the heck would anyone need to ask for specific values about their exact ages for that when the travelling ones must be younger in all possible illustrations of case 1?

Case 2: galaxy speeds = a fraction under c; travelling multuplets' speed, a much wider range, some much higher speed than the galaxies, but some of them will be moving at zero speed, and we only need to find one of those to see that his age is much greater than that of the stay-at-home multuplets in our galaxy which have hardly aged at all while the travelling ones moving in one particular direction have aged more by the same amount as the stay-at-home multuplets in case 1, so we're seeing the exact opposite result. Again, why the heck would anyone need to ask for specific values about their exact ages for that when this subset of the travelling multuplets must be older in all possible illustrations of case 2?

Either you should accept that or you should provide your numbers for a counterexample which breaks the above claims. No amount of me giving you specific numbers for cases which conform to the above claims will be worth anything, so you're just asking me to waste my time. No one in mathematics would ask me to do such pointless number crunching when there is no possibility of the results going against the above claims. It's trivial to do as well, but I refuse to waste battery power running a calculator even for a few seconds to do something so utterly ridiculous that no one with any self-respect should be demanding that anyone else do.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 27/08/2020 00:33:18
Quote from: Halc
Now now, the condition is that the galaxy is stationary as you defined above.
There are two cases, and you're homing in on the one that doesn't directly show up anything. You have to look at the other case that you see what matters here.
There is no other case. The FLRW model doesn't allow for a fast moving object unless it has recently accelerated. There's nothing in existence massive and energetic enough to accelerate an entire galaxy to significant speeds, so there is no other case.  Hence my firing the clock out of the galaxy. Acceleration at some point is necessary.  12 billion years ago isn't 'recently', so it will not pass us by at any particularly great velocity, as per the FLRW solution to Einstein's field equations.

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Computations please.  You make it sound like some other theory predicts different numbers.
You should be able to fit your own numbers to it without needing help from me.
I'm not the one making a claim about a difference in a pair of theories. You're the one claiming some sort of inconsistency with a theory. You should be able to show where the numbers don't work out. I should be able to show the errors in your calculations, but I've seen none.

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I gave you numbers. "Much younger" contains a number. "Ages more" contains a number.
Fair enough.  GR predicts the clock will have less than 12 billion years on it when it gets here.  No contradiction so far.  Not sure what you consider to be 'much less'.  My gut says maybe 9-10 billion years on the clock, but that's just my gut. That doesn't sound like 'much less'.

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In case 2, the speed of the galaxies is any high relativistic speed, so you can make that anything from 0.99999999c or 0.9c.
But no theory posits a galaxy moving at a speed like that, except in a local exotic inertial frame (such as the inertial frame of a muon striking Earth), which, being local, is pretty meaningless at a larger scale. The muon was recently accelerated. The galaxy cannot be.

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I don't know why you want me to choose specific numbers when I'm giving you a free choice.
I did choose.  I said relative speed between the clock and the galaxy that ejects it is arbitrarily close to light speed. I chose a case where it gets here now given a ballistic trajectory from a point in time when the universe appears 1.7 GY old. I specifically pushed it that far back so that the clock wasn't 'recently accelerated'.
I used a clock since that is a better indication of age than that of a hypothetical immortal human. Not sure why there needs to be observers travelling with clocks, but you can add them if you want.

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In case 2, all the multuplets are created at the same time again
No, they're not created at the same time since you're not ordering their ages in the same way as the FLRW coordinate system. In any inertial frame, the ages multuplets from case 1 are all out of sync. Or are you unware of RoS?

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Case 1: the galaxies are stationary. The multuplets ejected from them at 0.999...c practically stop aging as they travel through space, so when multuplets pass us, we see them in an ancient state.
Oopsie. This only happens in a SR universe, and you said you were not using that model.  And we would see them in a very young state, almost no time on the clocks.
Use a model where the universe is expanding. They'll pass by quite slowly, and have billions of years on their clocks.

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Case 2: the galaxies are moving at 0.999...c.
No theory allow this, not LET and not GR. Of course it will fail.

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Some of he multuplets ejected from them are moving through space at zero, and when we run across them we can see that we are the ones in an ancient state compared to them.
Oopsie again. What they see is objective fact, and cannot differ just due to an abstract coordinate change. If your theory predicts the above statement, then it is wrong. They will see our unaccelerated clocks with more time on them than on their accelerated clocks. Acceleration is objective after all.

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you fall in line behind [establishment nonsense] instead of trusting your own mind.
I trust my mind fine. I've not looked at any websites or anything during this discussion. I've managed to point out several mistakes in your 'numbers' above, mostly due to failure to apply RoS through a coordinate system change. You're making amateur mistakes.

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Case 1: galaxy speeds = 0. Travelling multuplets' speed, a fraction under c. Age of all travelling multuplets is much younger than the stay-at-home multuplets in the galaxies they're passing.
They'd have to continuously accelerate to do something like that. But they're posited as being ballistic, so this isn't true. There are galaxies that their light will reach but their ballistic selves will never reach, which would not be true if all these galaxies are flying by in pretty much negligible time. There are further galaxies that even their light would never reach, which would not be true in any universe described by STR at a large scale. Even continuously accelerating observers could never reach these galaxies since there is no way to overtake their own light which cannot reach them.

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Why the heck would anyone need to ask for specific values about their exact ages for that when the travelling ones must be younger in all possible illustrations of case 1?
Because your assertions are wrong, and numbers show this better than talk. Otherwise I wouldn't much need it.

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Again, why the heck would anyone need to ask for specific values about their exact ages for that when this subset of the travelling multuplets must be older in all possible illustrations of case 2?
Because you did a frame change and still asserted that all their ages were the same. RoS says that cannot be.  FLRW says nothing is capable of accelerating a galaxy to the kinds of speeds you're talking about.  If it cannot accelerate, and the mass/energy from which it is composed has existed since the big bang, then it is still stationary.  Motion slows under FLRW coordinates, which is why nothing can move fast for long, and why the clock will pass us by at a sedate speed no matter the power of the explosion that sent the thing our way.

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Either you should accept that or you should provide your numbers for a counterexample which breaks the above claims.
I did. I said 'no fast galaxies' and 'sedate speed'.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 27/08/2020 19:56:06
Quote from: Halc
Now now, the condition is that the galaxy is stationary as you defined above.
There are two cases, and you're homing in on the one that doesn't directly show up anything. You have to look at the other case that you see what matters here.
There is no other case.

Of course there's another case. There are two possible cases, and both of them can be combined into a single case, which is how the proof works. If you aren't prepared to try to understand case 2 for ideological reasons, you're rendering yourself incapable of grasping a crucial part of the the method.

When we're dealing with case 1 where the multuplets are all formed in systems that aren't moving at relativistic speed, they're intelligent enough to see what you keep missing, which is the thing that I came up with in the space of ten seconds two days ago and which you still haven't caught up with. They realise that even if they're in  a case 1 universe, they can create case 2 within it. They all have the wit to send out travelling multuplets at relativistic speeds in many directions, and those travelling multuplets then send out clocks at relativistic speeds relative to them in many directions. Each of those clocks comes with recorded details of its past. Set A of the travelling multuplets are all the ones moving along parallel paths aligned with the direction we call north. Each of them will have defined that direction with reference to distant objects in the universe straight ahead of and behind them, and the name "set A" is applied to them retrospectively when they've been grouped with others moving along parallel paths. The same documentation is carried by all the clocks that they send out. Some of those clocks will be sent out ahead at even higher relativistic speed, but others will be sent out behind and will end up with non-relativistic speed. Set A of multuplets and the clocks sent out by that set serve as a case 2 scenario within a case 1 scenario.

Ten seconds is all it took for me to spot this, and I didn't have anyone else spelling it out to help me, so what's taking you so long? But you're still the fastest mind I've found to discuss this kind of thing with.

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I'm not the one making a claim about a difference in a pair of theories. You're the one claiming some sort of inconsistency with a theory. You should be able to show where the numbers don't work out. I should be able to show the errors in your calculations, but I've seen none.

You've been given numbers which are fully adequate. What's stopping you working with them? "More" is a number. "Less" is a number. Learn how to use them.

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I gave you numbers. "Much younger" contains a number. "Ages more" contains a number.
Fair enough.  GR predicts the clock will have less than 12 billion years on it when it gets here.  No contradiction so far.  Not sure what you consider to be 'much less'.  My gut says maybe 9-10 billion years on the clock, but that's just my gut. That doesn't sound like 'much less'.

If we go for really extreme speeds, you don't need to reach for a calculator at all to handle this. The high relativistic speed can be so close to c that we can just treat it as c and assume practically no aging at all for the object moving at that speed. Suppose the multuplets are all created a billion years after the big bong. Some of them are sent out in many directions at close to c. These travellers are encountered by other stay-at-home multuplets in other galaxies ten billion years later, and in case 1 they find that the travelling multuplets are a year old while the stay-at-home ones who meet them are ten billion years old. If it's case 2 though, it's radically different. The stay-at-home multuplets have aged a year while the travelling ones moving in some directions have aged ten billion years (while the ones moving in the opposite direction have aged only a fraction of a second). The case 2 result allows the absolute frame's identity to be pinned down to a small range. The case 1 result also does this, but it only becomes clear that this is so after you've realised that case 1 and case 2 have to be able to coexist in the same system.

The multuplets sent out from case 1 galaxies (when the universe is a billion years old) who immediately send out clocks in many directions become a case 2 system within a case 1 system. Set A of those multuplets can look at clocks passing them which were sent out by other set A multuplets and the find that the clocks in that set are aging faster then them if they're moving relative to them in one direction and slower than them if they're moving in the opposite direction. This provides a means to break relativity within a single system.

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But no theory posits a galaxy moving at a speed like that, except in a local exotic inertial frame (such as the inertial frame of a muon striking Earth), which, being local, is pretty meaningless at a larger scale. The muon was recently accelerated. The galaxy cannot be.

It doesn't matter that no theory suggests the galaxies are moving at relativistic speed, but LET says that they could be (while STR has difficulty doing the same because it wants everything to be stationary and plays illegal frame-changing games to try to make that so). The proof doesn't depend on galaxies moving that fast, but that case must be considered as a possible reality. Even then, the proof still doesn't depend on them moving that fast because it doesn't need fast-moving galaxies to create a case 2 system. It can make a case 2 system within a case 1 system by sending out multuplets at relativistic speed who then send out clocks at what look to them like relativistic speeds.

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I don't know why you want me to choose specific numbers when I'm giving you a free choice.
I did choose.  I said relative speed between the clock and the galaxy that ejects it is arbitrarily close to light speed. I chose a case where it gets here now given a ballistic trajectory from a point in time when the universe appears 1.7 GY old. I specifically pushed it that far back so that the clock wasn't 'recently accelerated'.

I have no problem putting numbers to this, and you shouldn't have any either. I'm not going to complete your calculations for you when it's so obvious that the results will confirm what I've said.

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I used a clock since that is a better indication of age than that of a hypothetical immortal human. Not sure why there needs to be observers travelling with clocks, but you can add them if you want.

They are essential to create a case 2 system within a case 1 system. If you only have a case 2 system, you only need to see the age of multuplets passing you to be able to pin down the absolute frame. If you have a case 1 system you can actually do the same thing, but you don't necessarily realise that until you think things through with a case 2 system created within a case 1 system where you can then appreciate that you can't have a case 1 system within a case 1 system where the two case 1 systems are moving relative to each other. One of them has to be a case 2 system, and the existence of a case 2 system allows you to pin down the absolute frame. All case 1 systems are capable of hosting a case 2 system, so in all systems you can pin down the absolute frame, though it's tricky to do and takes a long time. The next step is to try to reducing the time needed to run an experiment of this kind to see if it can be turned into one that could be done within the space of a few decades rather than needing billions of years, but it may not be possible without the help of intelligent aliens in other galaxies who can serve as other groups of multuplets, and it may be impossible to get the results in less than hundreds of billions of years given how long it's actually going to take before we can all begin the experiment.

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In case 2, all the multuplets are created at the same time again
No, they're not created at the same time since you're not ordering their ages in the same way as the FLRW coordinate system. In any inertial frame, the ages multuplets from case 1 are all out of sync. Or are you unware of RoS?

They are all created at around the same time after the big bang. We aren't using the time of a skewed frame: we have an expanding universe with an even expansion across the part of the universe we're using, and with the galaxies all moving in such a way that they're close to being at rest in space rather than moving through it at relativistic speed, they are aging at the same rate and starting the experiment the same length of time after the big bang in each galaxy.

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Case 1: the galaxies are stationary. The multuplets ejected from them at 0.999...c practically stop aging as they travel through space, so when multuplets pass us, we see them in an ancient state.
Oopsie. This only happens in a SR universe, and you said you were not using that model.  And we would see them in a very young state, almost no time on the clocks.

This happens in an LET universe. It happens in our universe - we know that because we've tested it. Those multuplets will have their functionality practically halted as they move at c. STR also requires them to age hardly at all between leaving one galaxy and arriving at another. These assessments of ages are also not things that vary for different observers: all observers see them as being the same specific age when they arrive at another galaxy. The same traveller on reaching galaxy X cannot be seen as being older than the native multuplets of that galaxy by one observer and younger than them by another observer. The measured ages are invariant facts.

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Use a model where the universe is expanding. They'll pass by quite slowly, and have billions of years on their clocks.

If you're imagining the travellers slowing down and aging a lot as a result, then that's fine: they're still going to be moving faster through space than the stay-at home multuplets and will age less than them in case 1, whereas in case 2, they would age more than the stay-at-home ones.

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Case 2: the galaxies are moving at 0.999...c.
No theory allow this, not LET and not GR. Of course it will fail.

LET does allow for it. The lack of any obvious mechanism for all the galaxies being made to move so fast straight out of the big bang doesn't allow us not to consider the possibility of it happening, but again we don't need to rely on being in a case 2 universe because we can create a case 2 system within a case 1 universe, and that's why you should make the effort to understand how a case 2 system works instead of failing to do the necessary thinking on the basis that you don't believe a case 2 universe can happen. We don't need it to happen, but to understand the proof, you need to get your mind round it regardless and stop sabotaging your own thinking.

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Some of he multuplets ejected from them are moving through space at zero, and when we run across them we can see that we are the ones in an ancient state compared to them.
Oopsie again. What they see is objective fact, and cannot differ just due to an abstract coordinate change. If your theory predicts the above statement, then it is wrong. They will see our unaccelerated clocks with more time on them than on their accelerated clocks. Acceleration is objective after all.

Ten seconds, it took for me to see the whole thing. I'm not going to call it two days for you as that would be unfair, but given the amount of writing you've now done about this, we're talking about a good few minutes. What they see is facts agreed on by all observers. In a case 1 system, the travellers all age less than the non-travellers. In a case 2 system, some of the travellers age less than the non-travellers, and this is measured by all observers (after the fact, when images of the travellers meeting the non-travellers reach them). We're not making any coordinate change: we're dealing with single systems in which we either get a case 1 result or a case 2 result. And if we set up a case 2 system within a case 1 universe, we can see case 2 results and use them to pin down the absolute frame.

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I trust my mind fine. I've not looked at any websites or anything during this discussion.

You've brought all that establishment baggage along for the ride and it's hampering your efforts to understand the proof.

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I've managed to point out several mistakes in your 'numbers' above, mostly due to failure to apply RoS through a coordinate system change. You're making amateur mistakes.

On the contrary, you have found no mistakes in my numbers, but have merely mauled the maths. You are the one making amateur/professional mistakes.

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Case 1: galaxy speeds = 0. Travelling multuplets' speed, a fraction under c. Age of all travelling multuplets is much younger than the stay-at-home multuplets in the galaxies they're passing.
They'd have to continuously accelerate to do something like that. But they're posited as being ballistic, so this isn't true.

We don't need to care about them slowing down: they are going to be moving faster than their stay-at-home equivalents in case 1 thoughout their trips, and some of them will be moving slower than their stay-at-home equivalents in case 2 throughout their trips. The age differences will thus reverse between the two cases regardless of this factor.

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There are galaxies that their light will reach but their ballistic selves will never reach, which would not be true if all these galaxies are flying by in pretty much negligible time.

We don't need them to be able to travel from every galaxy to every other galaxy. It is sufficient for some of them to make a trip between two galaxies taking long enough to do so for the age differences to show up. I've been talking about billions of years, but if the speeds of travel are close to c and the universe is young with the galaxies close together, and if the timers are accurate, we can use much shorter trips. All that matters is that enough travellers meet enough non-travellers for us to get the data we need about their relative ages. This experiment could have be done in a small chunk of an observable universe. It's like with the Michelson-Morley experiment: if we want to show it visually in a software demo, we might have it travel at 0.866c to provide a clear understanding of what's going on, but in real life we move it at very low speed and depend on high-precision measurements instead. The same applies here: I've illustrated the idea using a thought experiment that uses extreme speeds to help people visualise it, but in the real world it would be done with low speeds and we'd be looking to use very accurate timers instead of just looking at multuplets and trying to assess their age by how gray their hair is.

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Why the heck would anyone need to ask for specific values about their exact ages for that when the travelling ones must be younger in all possible illustrations of case 1?
Because your assertions are wrong, and numbers show this better than talk. Otherwise I wouldn't much need it.

My assertions are right, and there are no numbers that can overturn that.

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Again, why the heck would anyone need to ask for specific values about their exact ages for that when this subset of the travelling multuplets must be older in all possible illustrations of case 2?
Because you did a frame change and still asserted that all their ages were the same.

No - I gave you two different cases involving different universes to illustrate the two possibilities. I then combined the two cases within a single universe, and observers using all frames agree about the relevant facts there about the relative ages of multuplets when they meet up.

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RoS says that cannot be.  FLRW says nothing is capable of accelerating a galaxy to the kinds of speeds you're talking about.  If it cannot accelerate, and the mass/energy from which it is composed has existed since the big bang, then it is still stationary.  Motion slows under FLRW coordinates, which is why nothing can move fast for long, and why the clock will pass us by at a sedate speed no matter the power of the explosion that sent the thing our way.

That's all barking up the wrong tree. You've fixated on trying to rule out case 2 instead of focusing on understanding its rules, and the result is that you never understood that the direction the proof is driving in is that can we recreate a case 2 system within a case 1 universe and use that to pin down the absolute frame.

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Either you should accept that or you should provide your numbers for a counterexample which breaks the above claims.
I did. I said 'no fast galaxies' and 'sedate speed'.

You should have got beyond that irrelevant objection within the first few seconds.
Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 28/08/2020 00:19:06
Of course there's another case. There are two possible cases, and both of them can be combined into a single case, which is how the proof works.
OK, but you need to fix the RoS mistakes you make that I pointed out, not a trivial task under GR.
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Set A of the travelling multuplets are all the ones moving along parallel paths aligned with the direction we call north.

Each of them will have defined that direction with reference to distant objects in the universe straight ahead of and behind them, and the name "set A" is applied to them retrospectively when they've been grouped with others moving along parallel paths. The same documentation is carried by all the clocks that they send out. Some of those clocks will be sent out ahead at even higher relativistic speed, but others will be sent out behind and will end up with non-relativistic speed. Set A of multuplets and the clocks sent out by that set serve as a case 2 scenario within a case 1 scenario.

Ten seconds is all it took for me to spot this, and I didn't have anyone else spelling it out to help me, so what's taking you so long? But you're still the fastest mind I've found to discuss this kind of thing with.
So far so good, but you haven't got to the point where you assert that all the case-2 clocks carried by the 'stationary' observers are somehow still in sync. I got what you're describing, but you falter on that point, and draw conclusions based on an assumption that their clocks will be in sync in some (what??) coordinate system.   In what sort of coordinate system are all these observers all stationary?  You need to find a solution to the Einstein equations which combine FLRW spacetime with relativistic motion, and neither of us is up to that task.
Also, I object to your term 'multiplets' which implies that they are all twins born at the same time and place, which is violated by you putting them all in different galaxies without explanation of how they got separated like that. So I'm using the more accepted term 'observer'.
Quote from: Halc
My gut says maybe 9-10 billion years on the clock, but that's just my gut. That doesn't sound like 'much less'.
I must retract this. Apparently the traveler clock reads a minimal value. I ran some numbers, and it seems I made some invalid assumptions.
So I throw a rock at 0.4c to the north. Somewhere 5.4 GLY north is a galaxy receding at that pace, so in a way, the rock is stationary relative to that galaxy.  But as time goes on, the Hubble 'constant' changes to a lower value, which increases the velocity of our rock relative to that distant galaxy from zero to something positive. That's the part I didn't take into account, that something could accelerate without force relative to the distant thing. So it eventually gets there, and seemingly will pass it at 0.4c, not something less as my initial thoughts suggested.

So, OK, I'm willing to say that the clock arriving from 12 billion years ago still reads a tiny time, and flings by us at nearly c. Still working it out, but this seems the more plausible answer now.

The ages at any meeting of observers are objective events, so both case 1 and case 2 must yield identical results.  The traveling observers see the galaxies fly by in moments, their separation contracted to very short distances. But each takes longer than the next to go by, and eventually no more galaxies are witnessed passing the window. There's a finite number of them, then no more.  This can take say an hour on his clock if his initial acceleration is enough.

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If we go for really extreme speeds, you don't need to reach for a calculator at all to handle this.
You do if you want to do the coordinate translation.

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The high relativistic speed can be so close to c that we can just treat it as c and assume practically no aging at all for the object moving at that speed.
I'll agree to that.
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Suppose the multuplets are all created a billion years after the big bong.
;D :P
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Some of them are sent out in many directions at close to c. These travellers are encountered by other stay-at-home multuplets in other galaxies ten billion years later, and in case 1 they find that the travelling multuplets are a year old while the stay-at-home ones who meet them are ten billion years old.
Those are objective (not coordinate system dependent) observations, so that will be observed in case 2 as well. You don't seem to realize that.
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If it's case 2 though, it's radically different.
Because you're doing it wrong. The observations are in fact identical, as they must be. I've pointed out where you go wrong.  OK, we'll go with the traveler aging one year, and the stay-at-home guy 10 GY.
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The stay-at-home multuplets have aged a year
No, in both cases, the accelerated guy ages a year, who is apparently stationary in case 2  How long the stay-at-home guy ages depends on your coordinate system, but you're using a Minkowskian transformation over a coordinate system that isn't Minkowskian. You can't apply SR to this situation. You explicitly specified using constant cosmological time for the the frame in case-1, not some Minkowskian inertial frame. You cannot translate freely between the two.

Maybe if you keep the experiment local, it would make more sense because you could reduce it to a simple SR case.  Two planets stationary in the cosmological frame (unaccelerated since the big bang when their clocks were set to zero) 10 LY apart, and a guy that travels between them in one subjective minute.  Now you can use the simpler inertial mathematics, and indeed the planet guys each age under a microsecond in the traveler frame. So what?  He still observers each planet guy being 10 years older than the one on the planet he left. Increasing the scale to one that involves expansion just complicates what is a simple situation.
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The case 2 result allows the absolute frame's identity to be pinned down to a small range.
OK. This isn't news. The identity of that frame (called the comoving frame, or the cosmological coordinate system) has been well known for nearly 100 years. Surely you know this already. Calling it an absolute frame is a choice. The physics community simply identifies the foliation as the only one symmetrical at cosmological scales. It is overwhelmingly the choice of absolute frame for those that posit the meaningfulness of such a thing. It doesn't foliate all of spacetime, which seems to be a fatal flaw in declaring it to be absolute, but that's just my observation.
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If you only have a case 2 system, you only need to see the age of multuplets passing you to be able to pin down the absolute frame.
I can see that from Earth, no expensive experiment needed. It's been pinned down for a long time. Get with the program. The only thing different is that they don't call it that name.
For instance, the term 'peculiar velocity' is the velocity of something relative to that frame, and not to any other. Earth currently has a peculiar velocity around 0.14c.
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And if we set up a case 2 system within a case 1 universe, we can see case 2 results and use them to pin down the absolute frame.
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and the result is that you never understood that the direction the proof is driving in is that can we recreate a case 2 system within a case 1 universe and use that to pin down the absolute frame.
Twice more, your goal seems to be to pin down this one special coordinate system, which has already been done. Is that your point? I agree, such a frame has been identified. GR uses it. Can we go home now?
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The case 1 result also does this, but it only becomes clear that this is so after you've realised that case 1 and case 2 have to be able to coexist in the same system.
Agree. No problem.
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The multuplets sent out from case 1 galaxies (when the universe is a billion years old) who immediately send out clocks in many directions become a case 2 system within a case 1 system.
By defining case2 within case 1 like that, you seem to have defined a coordinate system with non-orthogonal axes which is the only way to keep all those different clocks in sync in this new case 2 coordiante system. Nothing wrong with that, but the mathematics is more complicated, and you have the axes so close to parallel that the tiniest change along the space axis will result in a massive change in the time axis. So the 10 BY change is expected in one year of time in this squashed coordinate system. But your conclusions assume orthogonal axes, where two events separated on a spatial line would have an unchanged coordinate on the other axes.
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Set A of those multuplets can look at clocks passing them which were sent out by other set A multuplets and the find that the clocks in that set are aging faster then them if they're moving relative to them in one direction and slower than them if they're moving in the opposite direction.
You lost me here. What case are we talking?  Who is Set A? The accelerated observers?  How can any clock overtake them if they all accelerated identically.
How is the tick-rate of the passing clock measured?  Using a local inertial frame, or by looking at a successive clock assumed to be synced with it? The two methods will yield vastly different numbers.
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Not sure why there needs to be [biological] observers travelling with clocks, but you can add them if you want.
They are essential to create a case 2 system within a case 1 system.
I cannot think of one thing that a human can do better in any of these scenarios that isn't better done with clocks, lasers, mirrors, and other machines. All the human does is read the numbers from the machines, which can be done via email. He just doesn't need to be there. In my universe, people aren't special, but that's just my bias against anthropocentrism.
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They are all created at around the same time after the big bang.
Relative to the cosmological frame, yes. Not relative to the case2 'frame' that you've not really worked out, but you seem suddenly to assume there's an inertial frame or something where all these observers are stationary (there isn't) and far worse, where their clocks are still in sync, said amateur mistake that seem to fall back on some kind of Newtonian thinking.
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We aren't using the time of a skewed frame: we have an expanding universe with an even expansion across the part of the universe we're using
Not in the case 2 frame it isn't. There's only the one frame that has even expansion, and it isn't an inertial one. This is what I mean by case 2 not being valid until you come up with a coordinate system that has the properties you claim of it. The one with the non-orthogonal curved axes was the best I could think of.  It is sort of a polar coordinate system except the polar axis is a very tight spiral instead of a straight ray. If you want to work with that, fine, otherwise, you need to come up with said solution to the field equations that satisfies your scenario.
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STR also requires them to age hardly at all between leaving one galaxy and arriving at another.
STR is inapplicable, but I agree that GR also describes this. It describes the time between galaxies to continuously increase, while STR would have them going by at a steady pace, never ending.
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These assessments of ages are also not things that vary for different observers: all observers see them as being the same specific age when they arrive at another galaxy. The same traveller on reaching galaxy X cannot be seen as being older than the native multuplets of that galaxy by one observer and younger than them by another observer.
Agree.
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Use a model where the universe is expanding. They'll pass by quite slowly, and have billions of years on their clocks.
If you're imagining the travellers slowing down and aging a lot as a result
I was, and I'm retracting that part. The Hubble constant isn't a constant, so apparently the peculiar velocity is maintained. I've been working out the numbers, and that bit didn't hold up.
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Case 2: the galaxies are moving at 0.999...c.
No theory allow this, not LET and not GR. Of course it will fail.
LET does allow for it.
Of course it doesn't. LET asserts an absolute frame, so the speed of any object is a property of the object, not a relation with an abstract frame. The speed of any galaxy is pretty much stopped under that view.
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Some of he multuplets ejected from them are moving through space at zero, and when we run across them we can see that we are the ones in an ancient state compared to them.
Oopsie again. What they see is objective fact, and cannot differ just due to an abstract coordinate change. If your theory predicts the above statement, then it is wrong. They will see our unaccelerated clocks with more time on them than on their accelerated clocks. Acceleration is objective after all.
Ten seconds, it took for me to see the whole thing. I'm not going to call it two days for you as that would be unfair, but given the amount of writing you've now done about this, we're talking about a good few minutes.
Well maybe you should take more than 10 seconds, giving you more time to realize that clocks synced in one frame are not synced in another.
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What they see is facts agreed on by all observers. In a case 1 system, the travellers all age less than the non-travellers.
In a case 2 system, some of the travellers age less than the non-travellers
Frame reference omitted big time. What manner of coordinate system is used to make this statement?  It seems to just be a 'case 2 system', which is not a description of a coordinate system. Case 1 used the cosmological frame. OK, I get that. But case 2 system is undefined, especially since you added all these travelers going every which way. Pick one maybe, and then describe how to relate the others, because in his local inertial frame, most of the other observers don't even exist.
I could not describe such a coordinate system, especially in 10 seconds. Your admission of this indicates you are not putting thought to your scenario, and seeming just using Newtonian physics with time dilation, as if that's all that relativity is. Of course you get contradictions using that. It's wrong.
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You've brought all that establishment baggage along for the ride
So I have, since it has withstood an insane amount of scrutiny. Nobody follows the dogma of established physics since there's not a buck in doing so. Fame and fortune is taken by those that find flaws in established theory, and especially those that propose theories that make better predictions. That's why LET gets no traction since it adds more premises without benefit of better predictions. Better predictions is what sells.
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On the contrary, you have found no mistakes in my numbers
Hmm....
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All that matters is that enough travellers meet enough non-travellers for us to get the data we need about their relative ages.
Can't do that unless they meet those non-travellers more than once, else they don't know the age of them (in their own frame) when they started. But you've made no mistakes in your numbers, so my pointing this out must be me not knowing my Newtonian mechanics properly.
So I meet a non-traveler on a planet and he's 10 billion and I'm a child. So he was born way before me. I've not shown anything else.
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some of them will be moving slower than their stay-at-home equivalents in case 2 throughout their trips. The age differences will thus reverse between the two cases regardless of this factor.
What do you mean by 'age differences'?  It's not like a pair of people ever meet more than once for an objective comparison, so if one is a year old and the other is 10 billion, it might just be because the one started out at a microsecond less than 10 billion. So what do you mean by those words, and what do you think that shows? Remember your coordinate references when answering. Oh right, you've not defined a coordinate system, so you can just make up nonsense.
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We don't need them to be able to travel from every galaxy to every other galaxy. It is sufficient for some of them to make a trip between two galaxies taking long enough to do so for the age differences to show up.
Agree. Why not just use a pair of stars 100 LY apart, stationary in the cosmological frame?  It makes the math so much simpler. Why the stupid big scale that forces these exotic coordinate systems?
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I've been talking about billions of years, but if the speeds of travel are close to c and the universe is young with the galaxies close together, and if the timers are accurate, we can use much shorter trips.
Putting it closer to the BB doesn't solve any of the problems since the GR math still needs to be used. The trick is to get away from that event. We're assuming we've already pinned down this special frame. It's really easy to do with a simple microwave measurement in say 6 places in the night sky.
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It's like with the Michelson-Morley experiment: if we want to show it visually in a software demo, we might have it travel at 0.866c to provide a clear understanding of what's going on, but in real life we move it at very low speed and depend on high-precision measurements instead.
High speed is fine with me. It's not like we're funding a real thing. My problem is the usage of curved coordinate systems that you don't understand, and the lack of known solutions to the field equations to allow a frame shift like you describe. Keep it local and the same thing can be demonstrated with simpler inertial coordinate systems.
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but in the real world it would be done with low speeds and we'd be looking to use very accurate timers instead of just looking at multuplets and trying to assess their age by how gray their hair is.
Which is why I use clocks right from the start instead of trying to measure time by the paint peeling from the walls. I still haven't figured out what function the biological observers fill, except to be low-resolution clocks.
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I gave you two different cases involving different universes to illustrate the two possibilities. I then combined the two cases within a single universe, and observers using all frames agree about the relevant facts there about the relative ages of multuplets when they meet up.
If they all agree, where's the contradiction? What are we trying to demonstrate again?  Oh right, pinpointing the special frame, which is as simple as a couple trivial measurements done from Earth. I'm not contesting that conclusion.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 29/08/2020 05:56:48
but you need to fix the RoS mistakes you make that I pointed out, not a trivial task under GR.

There are no such mistakes to fix. In case 1 there is a universe expanding from a big bang with the galaxies separating due to expansion of space between them, so they aren't moving at high speed through that expanding space fabric. The amount of time it takes for those galaxies to evolve is the same everywhere with none of them slowed by any significant speed of movement through space.

In case 2 it's similar, but all the galaxies are moving through the expanding space fabric at relativistic speed. It takes longer for them to evolve due to their slowed functionality, but again they all reach the same stages of development at the same time because they all have the same amount of slowed functionality.

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]So far so good, but you haven't got to the point where you assert that all the case-2 clocks carried by the 'stationary' observers are somehow still in sync. I got what you're describing, but you falter on that point, and draw conclusions based on an assumption that their clocks will be in sync in some (what??) coordinate system.

Set A of multuplets all set out from galaxies which are at rest and which are at the same stage of their evolution. All the multuplets in set A accelerate to relativistic speed in the same direction in an identical manner and their clocks slow identically. There is no way for them to go out of sync. (Indeed, the same applies to the clocks of all other travelling multuplets as they are all travelling from galaxies which are at rest, but we can't rely on being in a case 1 universe, so we should restrict ourselves to a single set to guarantee that their clocks are equally affected by whatever they do.)

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In what sort of coordinate system are all these observers all stationary? You need to find a solution to the Einstein equations which combine FLRW spacetime with relativistic motion, and neither of us is up to that task.

The correct coordinate system to use for this is one that expands with the universe. You should not be attempting to use one in which we are fixed in place while other galaxies are moving and where some (outside the observable universe) are moving through that grid at superluminal speeds.

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Also, I object to your term 'multiplets' which implies that they are all twins born at the same time and place, which is violated by you putting them all in different galaxies without explanation of how they got separated like that. So I'm using the more accepted term 'observer'.

What do you mean, "without explanation"? They are like twins precisely because they do all come into being at the same time. They were separated by the expansion of space having been created together at the big bang. It actually takes a bit of time after that before they form, but in a thought experiment we're entitled to have them form just a moment after the big bang, and then they're separated by large distances simply by the universe expanding while they remain at rest in space. This already destroys RoS.

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The ages at any meeting of observers are objective events, so both case 1 and case 2 must yield identical results.

But with case 2 you get a very different result because it's the galaxies that are moving fast while all the travellers moving in one particular direction are at rest, so for them the journeys take vast amounts of time and they arrive at galaxies where very little has had a chance to happen due to their almost completely frozen functionally.

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Those are objective (not coordinate system dependent) observations, so that will be observed in case 2 as well. You don't seem to realize that.

No - it can't be the same in case 2. We know this because we can build a case 2 system within a case 1 system, and those two systems operate at the same place. We have our case 1 galaxies and set A of travelling multuplets playing the role of case 2 galaxies, while the clocks sent out by the set A multuplets play the role of case 2 multuplets, and we're interested most in the clocks that they send back the way they came because they stop and hold station relative to the case 1 galaxies, so they actually represent case 1 galaxies. Set A multuplets (case 2 galaxies) pass case 1 galaxies and we see that these multuplets (case 2 galaxies) have aged less than the case 1 galaxies. When set A multuplets encounter clocks sent backwards by other set A multuplets, you're asserting that those clocks will also have to run slow, practically frozen functionally, and the set A multuplets will be much older than them when they meet them, but no: these clocks are effectively case 1 galaxies and the set A multuplets age more slowly than those, so they must age more slowly than that group of clocks too, so you're not allowed to have the galaxies age faster than the set A multuplets and the set A multuplets age faster than the clocks they sent out behind them (as soon as they left their galaxies) - these particular clocks effectively remain with their galaxies and must age at the same rate as them. Two clocks sitting side by side will tick at the same rate (ignoring the gravity well influences, but they're trivial - we're not putting any of our timers anywhere near a black hole).

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How long the stay-at-home guy ages depends on your coordinate system, but you're using a Minkowskian transformation over a coordinate system that isn't Minkowskian. You can't apply SR to this situation. You explicitly specified using constant cosmological time for the the frame in case-1, not some Minkowskian inertial frame. You cannot translate freely between the two.

If STR can't apply to this, it has no business being applied to our universe at all. We have galaxies which have all existed for the same length of time since the big bang and they provide the basis for a coordinate system which expands along with the universe That's the right coordinate system to use for this. If a multuplet moves from one galaxy to another at nearly c, no time will pass for it while it makes that trip, but the galaxies will age a lot, and that will show up clearly when it arrives at the next one. When it encounters a clock sent out behind from a fellow set A multuplet, that clock reveals that it has aged as much as the galaxies. The clock serves as a case 2 multuplet and the multuplet serves as a case 2 galaxy. The case 1 galaxies say to the case 1 multuplet, "you were the one who moved", and the case 2 galaxies (the multuplet) say to the case 2 multuplet (the clock), "I was the one who moved". They have pinned down the local absolute frame in their region of the universe.

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OK. This isn't news. The identity of that frame (called the comoving frame, or the cosmological coordinate system) has been well known for nearly 100 years. Surely you know this already. Calling it an absolute frame is a choice. The physics community simply identifies the foliation as the only one symmetrical at cosmological scales. It is overwhelmingly the choice of absolute frame for those that posit the meaningfulness of such a thing. It doesn't foliate all of spacetime, which seems to be a fatal flaw in declaring it to be absolute, but that's just my observation.

With this thought experiment though, we show that it is the absolute frame of the kind which objects can either be at rest in or moving through and where they have absolute speeds of motion through it which determine how fast their clocks tick. That's the bit that's news, and it's the mistake you made that hid that from you because you mistakenly thought the same observations would be made in case 2 as case 1, but you actually get the opposite result.

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Twice more, your goal seems to be to pin down this one special coordinate system, which has already been done. Is that your point? I agree, such a frame has been identified. GR uses it. Can we go home now?

This is about pinning down the absolute frame at a location. It isn't merely about pinning down a coordinate system.

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By defining case2 within case 1 like that, you seem to have defined a coordinate system with non-orthogonal axes which is the only way to keep all those different clocks in sync in this new case 2 coordiante system. Nothing wrong with that, but the mathematics is more complicated, and you have the axes so close to parallel that the tiniest change along the space axis will result in a massive change in the time axis. So the 10 BY change is expected in one year of time in this squashed coordinate system. But your conclusions assume orthogonal axes, where two events separated on a spatial line would have an unchanged coordinate on the other axes.

I don't know where you're getting all that imagined complexity from. We simply have set A multuplets moving "north" relative to galaxies and set-A-south clocks which are at rest relative to the galaxies. It's really simple. We run the experiment and it tells us that the galaxies have an absolute speed of close to zero and the set A multuplets have an absolute speed close to c. If the experiment produces the opposite result, then we know that our galaxies are actually set 2 galaxies and that they have an absolute speed of nearly c while the set A multuplets have an absolute speed close to zero.

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Set A of those multuplets can look at clocks passing them which were sent out by other set A multuplets and the find that the clocks in that set are aging faster then them if they're moving relative to them in one direction and slower than them if they're moving in the opposite direction.
You lost me here. What case are we talking?  Who is Set A? The accelerated observers?  How can any clock overtake them if they all accelerated identically.

Multuplets were sent out from galaxies in all directions, but we're only interested in the ones that went north, and those are classed as set A. The multuplets all send out clocks in all directions once they're up to maximum speed themselves, and we're only interested in clocks sent out by set A multuplets, and we're most interested in the clocks that they send out southwards because those will then be at rest relative to the galaxies. That is how we put case 2 right on top of case 1 and show that they must have completely opposite results.

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How is the tick-rate of the passing clock measured?  Using a local inertial frame, or by looking at a successive clock assumed to be synced with it? The two methods will yield vastly different numbers.

We don't care about the tick rate: the Doppler effect will guarantee that we learn nothing from that. We only care about the time that the clock has measured, and the reading of that value when the clock meets a multuplet, or when a travelling multuplet meets a stay-at-home multuplet in a galaxy, will be the same for all observers. There is no option of that value being both smaller and bigger than the value on the clock of the other party.

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I cannot think of one thing that a human can do better in any of these scenarios that isn't better done with clocks, lasers, mirrors, and other machines.

Well, you need them to make clocks and to decide to do the experiment. You don't technically need to send any multuplets anywhere when you can just send clocks which then send out more clocks, but because this is akin to a twins paradox and that's traditionally done by sending a person, I've done the same here.

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They are all created at around the same time after the big bang.
Relative to the cosmological frame, yes. Not relative to the case2 'frame' that you've not really worked out, but you seem suddenly to assume there's an inertial frame or something where all these observers are stationary (there isn't) and far worse, where their clocks are still in sync, said amateur mistake that seem to fall back on some kind of Newtonian thinking.

In case 2 they are all moving at the same speed through space and in the same direction, so their clocks must remain in sync, so I'm not making any mistake. And case 2 can be created in case 1 as well: we have all our stationary galaxies which are only moving apart because the space between them is expanding, and we send out the travelling multuplets at the same time universally, and a moment after they've been sent out and reached nearly c, they send out their clocks, so all those clocks start their timings (in case 1) at the same universal delay after the big bang. The timings of those clocks will then diverge as they're going in lots of different directions with some stopping relative to the galaxies and others going much faster relative to the galaxies than the multuplets that sent them out. If you're working with a universe in which galaxies are moving apart because the space between them is expanding rather than because they are moving at different speeds through space, there is no mechanism to make their clocks run at different rates relative to each other so they will all age the same as each other whether they're in a case 1 system or a case 2.

[Post too long - needed to be split...]
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 29/08/2020 05:57:47
Part 2 of a split post:-

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We aren't using the time of a skewed frame: we have an expanding universe with an even expansion across the part of the universe we're using
Not in the case 2 frame it isn't. There's only the one frame that has even expansion, and it isn't an inertial one. This is what I mean by case 2 not being valid until you come up with a coordinate system that has the properties you claim of it.

A case 2 system can exist within case 1, so you have the same non-skewed frame for both. The expansion is identical. The only difference is that the galaxies are all moving north.

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STR also requires them to age hardly at all between leaving one galaxy and arriving at another.
STR is inapplicable, but I agree that GR also describes this.

STR comes into this because it denies the existence of absolute speeds, so if it's to apply to the universe at all, it should be testable in this experiment. STR says that the traveller is aging less than the stay-at-home by magic and that the stay-at-home is also aging less than the traveller by magic at the same time. However, we have results that show that some stay-at-homes age definitively more, and that other stay-at-homes age definitively less. The travelling multuplet in case 1 serves a stay-at-home in case 2. All our case 2 travellers (set A's south-sent clocks) are aging more than their stay-at-homes, and they're doing that by having lower absolute speeds. We know here that if we run a local twins paradox experiment with a travelling twin leaving a galaxy with a set A travelling multuplet where we have already established that a set A travelling multuplet ages less than the galaxy, then we know for certain that the travelling twin's clock is ticking slower than the galaxy's clocks too on the outward leg of his trip, and the same for the return leg. We can also do this with a stay-at-home twin who is moving along with the set A multuplet while a travelling twin accelerates to remain with the galaxy for a while before chasing to catch up. On the first leg of his trip, we know for certain that his clock was ticking faster than the stay-at-home twin's clock. This shows that STR does not fit our universe.

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Case 2: the galaxies are moving at 0.999...c.
No theory allow this, not LET and not GR. Of course it will fail.
LET does allow for it.
Of course it doesn't. LET asserts an absolute frame, so the speed of any object is a property of the object, not a relation with an abstract frame. The speed of any galaxy is pretty much stopped under that view.

Of course LET allows it, exactly as it allows the set A multuplets move through the absolute frame in case 1. In case 2, the galaxies do exactly what the multuplets do in case 1.

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Well maybe you should take more than 10 seconds, giving you more time to realize that clocks synced in one frame are not synced in another.

Ten seconds was sufficient. We don't need to care about what incorrect frames assert about clock synchronisation, and even if we've pinned down the absolute frame, we don't misuse of LET by ignoring the expansion of space and making out that the rest of the universe has slower functionality because it's moving relative to us. We take the expansion into account and correct for that.

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What they see is facts agreed on by all observers. In a case 1 system, the travellers all age less than the non-travellers.
In a case 2 system, some of the travellers age less than the non-travellers
Frame reference omitted big time. What manner of coordinate system is used to make this statement?

These are observations made by all observers regardless of any frame they're misusing.

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It seems to just be a 'case 2 system', which is not a description of a coordinate system. Case 1 used the cosmological frame. OK, I get that. But case 2 system is undefined, especially since you added all these travelers going every which way. Pick one maybe, and then describe how to relate the others, because in his local inertial frame, most of the other observers don't even exist.

Case 1 and case 2 can operate in the same place and share the same objects with different names attached to them. The set-A south-sent clocks and the galaxies are essentially interchangeable. This was the 10 second idea, and it stands up well three days on.

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I could not describe such a coordinate system, especially in 10 seconds. Your admission of this indicates you are not putting thought to your scenario, and seeming just using Newtonian physics with time dilation, as if that's all that relativity is. Of course you get contradictions using that. It's wrong.

The ten seconds was how long it took to spot this trick. I spent a lot more time checking it afterwards to make sure it worked, and it does work. You already can't have STR for reasons of all the other disproofs, but this is a particular way in which you cannot have it along with a universe that expands - that destroys STR by introducing demonstrable absolute speeds.

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You've brought all that establishment baggage along for the ride
So I have, since it has withstood an insane amount of scrutiny.[/quote]

It hasn't survived it any more than the impossible Gods of religions have survived being disproved. You simply have a vast number of deluded people clinging to broken models and brainwashing everyone about how the universe supposedly works and insulting other people who point out the fatal faults, shouting them down and calling them crackpots while systematically trying to hide all heretical discussion through deletions, bans, and throwing threads into special forums filled with so much crackpot action that no one normal ever reads them. That's not withstanding scrutiny, but running away from it.

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Nobody follows the dogma of established physics since there's not a buck in doing so.

Same with religion, unless you're a superpreacher. Physics has a good few of those.

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Fame and fortune is taken by those that find flaws in established theory, and especially those that propose theories that make better predictions. That's why LET gets no traction since it adds more premises without benefit of better predictions. Better predictions is what sells.

LET is infinitely simpler as it removes all the magic where contradictions have to be tolerated, and it doesn't break at every turn by generating event-meshing failures, and it allows for real causation rather than depending on infinite magic to account for fake causation, and it also makes better predictions because it doesn't produce nonsense about what goes on in black holes.

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All that matters is that enough travellers meet enough non-travellers for us to get the data we need about their relative ages.
Can't do that unless they meet those non-travellers more than once, else they don't know the age of them (in their own frame) when they started. But you've made no mistakes in your numbers, so my pointing this out must be me not knowing my Newtonian mechanics properly.

The method doesn't depend on meeting anyone repeatedly. It's sufficient that the details of who aged how much from all these encounters all tell the same story about which frame is the local absolute frame.

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So I meet a non-traveler on a planet and he's 10 billion and I'm a child. So he was born way before me. I've not shown anything else.

You need to be patient and wait for more data to come in. But if this experiment had been started nearer to the time of the big bang, we could have been collecting that data for billions of years as travellers pass us and tell us about their encounters with clocks sent out by their own set. We don't have the data, but we do have this thought experiment, and it tells us that this could be done and that it would give us a result that lets us pin down the absolute frame.

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some of them will be moving slower than their stay-at-home equivalents in case 2 throughout their trips. The age differences will thus reverse between the two cases regardless of this factor.
What do you mean by 'age differences'?  It's not like a pair of people ever meet more than once for an objective comparison, so if one is a year old and the other is 10 billion, it might just be because the one started out at a microsecond less than 10 billion.

All the multuplets set out the same length of time after the big bang. All set A's clocks were sent out soon after, again the same length of time after the big bang as each other. If it's a case 1 universe with stationary galaxies, the set A south-sent clocks are stationary too while the multuplets are moving at close to c. If it's a case 2 universe, some of the multuplets are stationary (and we retrospectively call them set A after we have the results in) while their south-sent clocks are moving south with the galaxies at nearly c. A microsecond difference of timing when something's moving at nearly c will be a long delay, but if you collect enough data and average it out, clear differences will show up. But in case 1 you can't get a significant difference anyway as everything's functioning fast until the multuplets are sent out, and in case 1 you also get all the results you need just from looking at how young they are when they arrive at other galaxies. It's with sending out the clocks to create case 2 within case 1 that you'll get small differences in timings adding up to huge differences, but because the clocks whose timings you depend on most are at rest relative to the galaxies, you can see that any variations in their ages are related to how far they were released out from their home galaxy, so it's easy to correct for that. In case 2, all the galaxies are slowed enormously, so there could be big delays between multuplets being sent out as measured by the travelling multuplets, but all of those galaxies have similar low values on their clocks, and all of the travelling multuplets moving in one particular direction have huge values on their clocks as the pass other galaxies compared with the values on the clocks of those galaxies - there might be a lot of variation in the times on those multuplets' clocks, but that doesn't matter, and they also record where they originated from, so you have a timing for the trip over a known distance. We'll have a clear reversal in the results between a case 1 universe and a case 2 one.

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So what do you mean by those words, and what do you think that shows? Remember your coordinate references when answering. Oh right, you've not defined a coordinate system, so you can just make up nonsense.

By older, I mean manifestly massively older, and by younger I mean manifestly massively younger - there will be no possibility of mixing them up. The coordinate system to use is obvious - you just have to allow it to expand with the universe.

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Why not just use a pair of stars 100 LY apart, stationary in the cosmological frame?  It makes the math so much simpler. Why the stupid big scale that forces these exotic coordinate systems?

We need to use locations which have expanding space between them. You won't register much of that over 100 LY. We use the expansion to separate a pair of twins, then we move one of them through space to reunite them, and when we do that, we pin down the absolute frame. If the travelling twin ages less, his absolute speed through space is higher that that of the stay-at-home twin. If he ages more than the stay-at-home twin though, his absolute speed must be lower than that of the stay-at-home twin.

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Putting it closer to the BB doesn't solve any of the problems since the GR math still needs to be used.

It would solve a problem if there had been lots of intelligent species about sooner to start carrying out the experiment in time for us to have collected lots of results now.

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The trick is to get away from that event. We're assuming we've already pinned down this special frame. It's really easy to do with a simple microwave measurement in say 6 places in the night sky.

In a case 2 universe, you'd expect the CMB to have the same skew as the galaxies which are all moving the same way at nearly c, so it would look to observers in those galaxies as if they're stationary if they assume the CMB data is a reliable guide to that.

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High speed is fine with me. It's not like we're funding a real thing. My problem is the usage of curved coordinate systems that you don't understand, and the lack of known solutions to the field equations to allow a frame shift like you describe.

There isn't one that I don't understand. You're just failing to work with the right one.

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Keep it local and the same thing can be demonstrated with simpler inertial coordinate systems.

If you try to do that, you either shut out the expansion that the thought experiment depends on or render the effect very small, and you then shackle yourself to a coordinate system that goes out of alignment with the absolute frame over distance. You need a frame that expands with the universe.

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I gave you two different cases involving different universes to illustrate the two possibilities. I then combined the two cases within a single universe, and observers using all frames agree about the relevant facts there about the relative ages of multuplets when they meet up.
If they all agree, where's the contradiction? What are we trying to demonstrate again?  Oh right, pinpointing the special frame, which is as simple as a couple trivial measurements done from Earth. I'm not contesting that conclusion.

What we're showing is that the case 2 galaxies age less than the case 2 travellers, while the case 1 galaxies age more than the case 1 travellers, and when we put a case 2 system in a case 1 universe, we discover that we can use these measurements to pin down the absolute frame, even if all we use are galaxies and primary travellers: if the travellers age less, we're in a case 1 universe, but if they age more, we're in a case 2 universe.
Title: Re: Is Special Relativity reciprocal?
Post by: phyti39 on 29/08/2020 18:58:23
David;
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These two flashes of light travel alongside each other all the way to the observer who sees them both arrive simultaneously. How did the two flashes of light know to travel at the same speed as each other? Did they decide to travel at c relative to one ship rather than the other ship?

Light does not propagate relative to an object!
The propagation speed of light in space is constant and INDEPENDENT of its source.
The big word being the most significant, meaning light does not acquire the speed of the source. This distinguishes light motion from material object motion.

In a plane moving at a constant speed v, every element in the plane has acquired the speed v.
As seen by an observer outside the plane:
With no air turbulence, if a passenger tosses a ball perpendicular to the aisle at speed w, to another passenger, the motions are simultaneous and add as vectors.
If the v component is removed from all elements within the plane, and the ball tossed in the same manner, the scenario would be equivalent to the plane being at rest on the ground. This demonstrates the equivalence of inertial motion and rest, and an example of SR postulate 1, the same description of physics is valid in all inertial frames.
It also shows a need for a definition of 'rest' different from that of Newton. There is only motion and 'rest' is a special case when two systems A and B, have identical velocities.
Thus each can be in motion while at rest relative to each other.

Replacing the plane with a spaceship moving at .1c, the ball with a photon, and a detector in the opposite seat, the simultaneous motions do not add as vectors.
As seen by an observer outside the ship:
The photon vector is rotated in the direction of the detector but at a constant speed c.
This results in a small gap between photon and detector, i.e. v and c don't meet. The photon spends a small portion of its energy chasing the detector, thus requires a little more transit time. As the ship moves faster nearing c, the gap becomes more significant.   

LET assumes an ether. SR postulate 2 assumes independent light propagation (AS IF  from a fixed position in space). Events do not move. Both produce the same results since the coordinate transformations are the same.
Einstein later replaced the redundant Lorentz ether with the gravitational field in GR, with a similar status as Newton's absolute space.

The MGP experiment
The motion can be represented as a cylinder with the ct axis through the origin, and d equal to the circumference. The cylinder is unrolled to a flat surface with only constant velocities, the origin (black) and light (blue). Light speed is constant in SR. The rotation is absolute motion, with the origin approaching in the cw direction and receding in the ccw direction.
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Einstein's insistence that the speed of light is always c relative to any observer is nothing more than a contrived mathematical abstraction

I can agree with you on this part but only within the correct context.
"That light requires the same time to traverse the same path A to M as for the path B to M is in reality neither a supposition nor a hypothesis about the physical nature of light, but a stipulation which I can make of my own freewill in order to arrive at a definition of simultaneity."
Relativity The Special and the General Theory
Albert Einstein 1961 Crown Publishers Inc. pg 23

The simultaneity convention has to satisfy the expectations of an observer at rest.

Assuming a pseudo rest frame is a choice, not a mandate.

Making measurements in motion, includes the effects of time dilation and length contraction, which result in measured light speed equal to c.
Are those effects included in your simulations?

When considering motion, light speed is c, object speed is v.
It is necessary to use the forms of c-v and c+v in calculations, as closing speeds, rates of change for a spatial separation. There is no physical thing moving at those speeds.

Title: Re: Is Special Relativity reciprocal?
Post by: phyti39 on 29/08/2020 19:10:53
Jano;

Consider the popular example of reciprocal time dilation.
A and B with a relative velocity, observe each other's clock rate as slower than their own. This is not a case of each watching the other clock and seeing doppler effects.
The red calibration curves denote a constant time where intersecting an observer time line.
With clocks set to t=0 at the origin, each sends a signal at t=1, which triggers the remote clock to send a time encoded signal which returns at t=2.15.
What is the basis for their conclusion?
The SR clock synch convention defines the light transit times out and back to be equal, which would be the expectation of a rest frame observer.
The (green) axis of simultaneity, established when synchronizing the clocks in each frame, assigns the distant clock event to a later time on the observers clock. Clock event 1.47 is assigned to (1+2.15)/2=1.58.
It's observer perception, what each thinks after all analysis is complete.
The variation in assigned times depends on the directions of the target and the signals, the same or opposite.
U would claim the B clock is running slower than the A clock.
What time is it? It depends on who you ask!
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Title: Re: Is Special Relativity reciprocal?
Post by: phyti39 on 29/08/2020 19:21:21
Jano:

simultaneity and length contraction required for reciprocity

SR requires both ends of an object be measured simultaneously.
A is black,  B is green, each ship is length d, g=gamma.
The near end of both ships are at 0 for all measurements.

left (with no length contraction):
A measures length of green ship as d, on his axis of simultaneity Ax.
B length/A length =d/d=1.
B measures length of black ship as e, on his axis of simultaneity Bx.
A length/B length =e/f=1/g^2.
Measurements are not reciprocal.

right (with length contraction):
A measures length of green ship as d/g, on his axis of simultaneity Ax.
B length/A length =1/g.
B measures length of black ship as e, on his axis of simultaneity Bx.
A length/B length e/f=1/g.
Measurements are reciprocal

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Title: Re: Is Special Relativity reciprocal?
Post by: Halc on 30/08/2020 01:57:53
There are no such mistakes to fix.
In that case youíre talking about your own new theory where simultaneity isnít frame dependent.  Thatís consistent for an absolutist, but having the galaxies being the thing moving is not consistent with the view.  So youíve alienated every view I can think of. If you find an inconsistency, it just means the new theory doesnít work so well.

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In case 2 it's similar, but all the galaxies are moving through the expanding space fabric at relativistic speed. It takes longer for them to evolve due to their slowed functionality, but again they all reach the same stages of development at the same time because they all have the same amount of slowed functionality.
Ö
The correct coordinate system to use for this is one that expands with the universe.
This is what I mean. I cannot think of any known coordinate system where this is the case, which is why Iíve said case 2 doesnít exist.  FLRW metric is such a solution, but that metric does not have frame rotation operators defined like SR does with Minkowski coordinates, so thereís just the one frame.
Youíre free to find a solution to Einsteinís field equations that satisfies all these conditions, but until then, thereís little to discuss about it.

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You should not be attempting to use one in which we are fixed in place while other galaxies are moving and where some (outside the observable universe) are moving through that grid at superluminal speeds.
FLRW metric does not have anything moving at superluminal speeds. Motion is defined as peculiar velocity in the metric, and that is bounded by light speed anywhere.

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But with case 2 you get a very different result because it's the galaxies that are moving fast while all the travellers moving in one particular direction are at rest, so for them the journeys take vast amounts of time and they arrive at galaxies where very little has had a chance to happen due to their almost completely frozen functionally.
This is wrong. Youíre using a Minkowskian property on a non-Minkowskian coordinate system. Youíre also denying Minkowskian RoS above, but still attempting to apply dilation with Minkowskian rules. Youíre not being self consistent.

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Those are objective (not coordinate system dependent) observations, so that will be observed in case 2 as well. You don't seem to realize that.
No - it can't be the same in case 2.
It must be. If objective observations are different from one case to the other, then one of the cases is wrong, which is what Iíve said from the beginning.

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If STR can't apply to this, it has no business being applied to our universe at all.
Much better.  And yet youíre trying to use it above, but incorrectly.

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With this thought experiment though, we show that it is the absolute frame of the kind which objects can either be at rest in or moving through and where they have absolute speeds of motion through it which determine how fast their clocks tick. That's the bit that's news
Itís not news. The general idea has been known for 90 years.  It still doesnít foliate all of spacetime, which suggests that there is no absolute frame at all. This is just a special one, but not necessarily absolute. If you want to demonstrate the latter, you need to find a valid way to falsify the view that there isnít one.

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This is about pinning down the absolute frame at a location. It isn't merely about pinning down a coordinate system.
A frame has a location? If not, whatís the difference between a coordinate system and a frame? Theyíre the same thing to my knowledge.

What are the absolute coordinates of our solar system? Seems funny to call it absolute if you canít answer that.  ď2nd star to the right and straight on till morningĒ is a relative reference for example.

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akin to a twins paradox and that's traditionally done by sending a person
Every physical demonstration of the twins scenario has been done with atomic clocks, never people.

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In case 2 they are all moving at the same speed through space and in the same direction, so their clocks must remain in sync so I'm not making any mistake.
Ouch. Why do I bother if this is your understanding?
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 30/08/2020 03:24:18
Light does not propagate relative to an object!

If it leaves an object or arrives at one, it has propagated relative to one at a speed greater then zero

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The propagation speed of light in space is constant and INDEPENDENT of its source.

And if the source is an observer, then that means it moves at speeds other than c relative to that observer, so you've already rejected part STR. Of course, STR does that too by saying two incompatible things and thereby contradicting itself.

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The big word being the most significant, meaning light does not acquire the speed of the source. This distinguishes light motion from material object motion.

Which is fine until you demand that it is c relative to all observers. It's when you want two incompatible things at once that your theory breaks.

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This demonstrates the equivalence of inertial motion and rest, and an example of SR postulate 1, the same description of physics is valid in all inertial frames.
It also shows a need for a definition of 'rest' different from that of Newton. There is only motion and 'rest' is a special case when two systems A and B, have identical velocities.
Thus each can be in motion while at rest relative to each other.

There are two ways of interpreting that. One of them has been disproved, and the other depends on "same" meaning that it looks the same and not that it is the same, as with LET.

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The MGP experiment
The motion can be represented as a cylinder with the ct axis through the origin, and d equal to the circumference. The cylinder is unrolled to a flat surface with only constant velocities, the origin (black) and light (blue). Light speed is constant in SR. The rotation is absolute motion, with the origin approaching in the cw direction and receding in the ccw direction.

You can represent it in lots of ways to try to hide what it actually reveals. I showed you what it reveals and that can't be undone.

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Are those effects included in your simulations?

Wherever they're relevant, yes.

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When considering motion, light speed is c, object speed is v.
It is necessary to use the forms of c-v and c+v in calculations, as closing speeds, rates of change for a spatial separation. There is no physical thing moving at those speeds.

Indeed, and the relative speeds (closing speeds) vary: that's why a ship at rest is different from a moving ship in the way that light travels about within it. The physics of what's happening within them is different, but if you try to measure each case while moving with it, they appear to be the same. This gives us two contradictory interpretations of what STR says, and some people try to use both of them, asserting that STR means one whenever the other is shown to be wrong, and then asserting things that depend on the disproved interpretation and justifying that interpretation on the basis of that interpretation being a viable interpretation of the words, even though it's only the other interpretation that holds. It's like a farmer who only has bulls expecting them to give birth to calves on the basis that a bull is a male cow and cows can give birth to calves.
Title: Re: Is Special Relativity reciprocal?
Post by: David Cooper on 30/08/2020 04:24:52
There are no such mistakes to fix.
In that case youíre talking about your own new theory where simultaneity isnít frame dependent.

When I find faults in someone else's theory, it doesn't become my theory on the basis that I label it as faulty while its owners put an incorrect label on it claiming it isn't faulty. There are two models in play here, and both belong to the establishment. One has an expanding universe with space expanding between galaxies and the other is STR. If the two models can't coexist, one of them does not describe our universe and belongs in the bin. If you want them both to fit, something's got to give. We have case 1 travellers aging less than case 1 stayers, and we have case 2 travellers aging more than case 2 stayers, and we have them all in the same system such that the case 1 travellers are the case 2 stayers and the case 2 travellers are the case 1 stayers. That is the necessary consequence of applying the rules of an expanding universe and also applying the rules of relativity. It enables the absolute frame to be pinned down and thereby eliminates STR which denies the existence of such a frame.

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Thatís consistent for an absolutist, but having the galaxies being the thing moving is not consistent with the view.  So youíve alienated every view I can think of. If you find an inconsistency, it just means the new theory doesnít work so well.

We don't have the galaxies moving in case 1 with a case 2 system set up within it, so we are not dealing with a new theory of any kind. We are revealing a fault in the establishments models: STR is not compatible with expanding space. You can't save both models. STR's the one to ditch anyway though as it's been disproved in so many ways already.

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The correct coordinate system to use for this is one that expands with the universe.
This is what I mean. I cannot think of any known coordinate system where this is the case, which is why Iíve said case 2 doesnít exist.  FLRW metric is such a solution, but that metric does not have frame rotation operators defined like SR does with Minkowski coordinates, so thereís just the one frame.
Youíre free to find a solution to Einsteinís field equations that satisfies all these conditions, but until then, thereís little to discuss about it.

Just use the coordinate system that I've described. The galaxies remain more or less at fixed locations while the distance between grid points grows over time while the universe expands. I don't see why you have a problem with that for case 2 and not with case 1 because they are identical other than that the content is moving, and in case 1 we can set some material moving in the same manner without anything breaking.

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]FLRW metric does not have anything moving at superluminal speeds.

I was referring to superluminal speeds relative to us. They are not doing superluminal speeds relative to their local space fabric, but are moving through that at close to zero speed.

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But with case 2 you get a very different result because it's the galaxies that are moving fast while all the travellers moving in one particular direction are at rest, so for them the journeys take vast amounts of time and they arrive at galaxies where very little has had a chance to happen due to their almost completely frozen functionally.
This is wrong. Youíre using a Minkowskian property on a non-Minkowskian coordinate system. Youíre also denying Minkowskian RoS above, but still attempting to apply dilation with Minkowskian rules. Youíre not being self consistent.

It is fully self-consistent. The whole point is that the Minkowskian stuff doesn't fit an expanding universe. I'm using the rules of the expanding universe to dictate how the galaxies and other things age, and then I'm using their encounters to show up which have aged more than which. Case 1 appears compatible with STR, in part at least, because the case 1 travellers age as predicted by STR, but STR gets the predictions wrong for case 2 (and this can be case 2 within case 1) due to the lack of symmetry in the system. STR is ruled out by this for our universe. Well, there is one trick you could try to use to make it look as it it's viable, but that means getting rid of the expansion and having all the galaxies move at different absolute speeds, and as soon as you try that, you have to throw out STR again for another reason. It's just a hopeless theory, and everyone should have seen that from the start because it rests on contradiction anyway. It was never viable.

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No - it can't be the same in case 2.
It must be. If objective observations are different from one case to the other, then one of the cases is wrong, which is what Iíve said from the beginning.

Case 2 travellers are case 1 stayers and case 1 travellers are case 2 stayers - they are interchangeable. When a case 2 traveller meets a case 2 stayer and finds that case 2 stayer to be older, we can translate that to: when a case1 stayer meets a case 1 traveller, he must find the case 1 traveller to be older. You are claiming that the stayer will be older in both cases, but that requires one clock to have two radically different times on it at the same time

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If STR can't apply to this, it has no business being applied to our universe at all.
Much better.  And yet youíre trying to use it above, but incorrectly.

I'm using it absolutely correctly. You're four days into this now and still haven't caught up with the bit in the previous paragraph where you don't realise you're requiring a clock to provide two different timings at the same time with one of those times many orders of magnitude greater than the other.

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With this thought experiment though, we show that it is the absolute frame of the kind which objects can either be at rest in or moving through and where they have absolute speeds of motion through it which determine how fast their clocks tick. That's the bit that's news
Itís not news. The general idea has been known for 90 years.  It still doesnít foliate all of spacetime, which suggests that there is no absolute frame at all. This is just a special one, but not necessarily absolute. If you want to demonstrate the latter, you need to find a valid way to falsify the view that there isnít one.

Clearly it is news, because it shows that STR is incompatible with an expanding universe. Every point in the universe must have an absolute frame in it. If you project the wrong kind of coordinate system out from that and find it goes out of sync with the absolute frame at other locations, then that's another error you're making. If you're requiring this kind of absolute frame to be the same frame as some external frame that doesn't expand and which might be more fundamentally absolute, then again you're making an error. We've discussed this before and you shouldn't still be mixing them up.

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This is about pinning down the absolute frame at a location. It isn't merely about pinning down a coordinate system.
A frame has a location? If not, whatís the difference between a coordinate system and a frame? Theyíre the same thing to my knowledge.

The comparison was between an absolute frame and a coordinate system; not any old frame.

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What are the absolute coordinates of our solar system? Seems funny to call it absolute if you canít answer that.  ď2nd star to the right and straight on till morningĒ is a relative reference for example.

Coordinates aren't part of the real universe: we just map them to it in an arbitrary way, so you can make the coordinates anything you like. You can do the same for a second object, then after that you have less choice. Once you've done it for a third object, all the rest may be forced.

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akin to a twins paradox and that's traditionally done by sending a person
Every physical demonstration of the twins scenario has been done with atomic clocks, never people.

Fine - it would be the same with this. And in thought experiments it's done with twins, which is why I've built this one in the same style.

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In case 2 they are all moving at the same speed through space and in the same direction, so their clocks must remain in sync so I'm not making any mistake.
Ouch. Why do I bother if this is your understanding?

What other understanding of it can there be? What extra factors are you imagining to make them age differently while they move at the same speed in the same direction? The model's very simple and I'm applying it. If you want to complicate the model to make it different from that, go ahead and try, but you'll just make a mess that doesn't fit our universe.
Title: Re: Is Special Relativity reciprocal?
Post by: phyti39 on 30/08/2020 16:23:51
Assuming the subject is still SR reciprocity,
Jano;

Here is another example of reciprocal time dilation.
The red line has been substituted for the calibration curve in the previous example, using the arc method for the one time needed.

On the left is A's description of B moving at .5c to right.
If A sent a signal at At=.500 to B, it would get a return time of Bt=.866.
A concludes the B clock is slow by a factor of .866.
B sends a signal at Bt=.289 and gets a return time of At=.500.

On the right is B's description of A moving at .5c to left.
B assigns the At=.500 to Bt=.577.
B concludes the A clock is slow by a factor of .500/.577=.866.
The td is reciprocal.

Using the coordinate transformations/LT,

x'=g(x-vt)=(0 - .5*.5000)/.866 = -.289

t'=g(t-vx)=(.500-.5*0)/.866 = .577

The answers agree with the spacetime graphics showing they are a geometric interpretation of the coordinate transformations.

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Title: Re: Is Special Relativity reciprocal?
Post by: xersanozgen on 06/09/2020 20:55:08
https://www.academia.edu/44028129/Special_Relativity_the_Clock_Absurdity


https://www.academia.edu/42973938/EINSTEINS_TERRIBLE_TWINS_and_Other_Tales_of_Relativistic_Woe?email_work_card=title

These papers may explain reciprocity in SR better.
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 16/09/2020 20:26:34
Gentlemen,
I need to catch up to the latest posts,
Jano
Title: Re: Is Special Relativity reciprocal?
Post by: Jaaanosik on 16/09/2020 21:01:31
Phyti,
how about the second leg of the blue light roundtrip?
It takes 2s in the stay home frame.
It takes 7s in the moving frame.
Do both observers agree on this analysis?
Does the moving observer agree with the stay home observer about the time analysis?
Jano


(https://i.imgur.com/AHfnpxw.png)