# The Naked Scientists Forum

### Author Topic: Is distance an absolute invariant?  (Read 16267 times)

#### alancalverd

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##### Re: Is distance an absolute invariant?
« Reply #250 on: 11/02/2016 09:52:49 »
k, my terminology is lacking.  I am talking about a reference frame that is moving relative to the observers reference frame at a constant velocity. Edit: that is faster relative to the observers reference frames constant velocity.
Almost!

We are nearly back to Reply #1. An observer moving with the stick (i.e. stationary in relation to the stick) sees the stick at its "proper" length, any other observer sees it contracted.

But "faster" is meaningless here because there is no universal reference frame. You can treat any constant velocity as zero, and the relativistic contraction is completely symmetric (you shrink in my eyes, I shrink in yours) if the relative velocity is constant.

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #251 on: 11/02/2016 09:56:40 »
k, my terminology is lacking.  I am talking about a reference frame that is moving relative to the observers reference frame at a constant velocity. Edit: that is faster relative to the observers reference frames constant velocity.
Almost!

We are nearly back to Reply #1. An observer moving with the stick (i.e. stationary in relation to the stick) sees the stick at its "proper" length, any other observer sees it contracted.

But "faster" is meaningless here because there is no universal reference frame. You can treat any constant velocity as zero, and the relativistic contraction is completely symmetric (you shrink in my eyes, I shrink in yours) if the relative velocity is constant.

If you are both travelling at the same speed relatively the objects cancel each other out.

#### alancalverd

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##### Re: Is distance an absolute invariant?
« Reply #252 on: 11/02/2016 09:57:44 »
What I do not understand is how come the Lorentz transformations form part of the GR field equations.  How are these concepts of special relativity and general relativity considerations being intertwined?

Because by definition GR must simplify to SR if there is no acceleration or gravitational field. SR is, as it says, a special case of R.

#### timey

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##### Re: Is distance an absolute invariant?
« Reply #253 on: 11/02/2016 09:58:25 »
Space Flow, if you take on board my scenario of an observer on a railway station platform, standing on a gravity machine that is reducing the observers gravitational field by the inverse square law with each train carriage that is passing at a constant velocity,  this is why I said the observed reference frame is moving faster than the observers reference frame.

No matter, I'm getting the info I want, I think (chuckle)

Susskind lectures tell me (I think) that the Lorentz transformations are used to describe the effects of time dilation and distance contraction in relation to velocity for matter.

Susskind lectures tell me (I think) that the Lorentz transformations are also used to describe the stretching of the fabric of space.  Is this correct?

I think you just confirmed this, right?  (Scratches head...(chuckle))

I get exactly where you are coming from about the equivalence principle.

Yes, established physics states that gravitational time dilation is apparent in a gravitational field.  If the field decreases, the rate of time increases.  Just to check, it is not the Lorentz transformations that describes this gravitational time dilation?  Right?

I'm going somewhere with this, but let me first check that I'm correct so far please...

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #254 on: 11/02/2016 09:59:41 »
What I do not understand is how come the Lorentz transformations form part of the GR field equations.  How are these concepts of special relativity and general relativity considerations being intertwined?

Because by definition GR must simplify to SR if there is no acceleration or gravitational field. SR is, as it says, a special case of R.

I thought Einstein had to make GR with maths to justify the fairy tale like SR?

#### alancalverd

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##### Re: Is distance an absolute invariant?
« Reply #255 on: 11/02/2016 10:00:20 »

If you are both travelling at the same speed relatively the objects cancel each other out.

Almost there! Same speed relative to what? I think you mean "stationary with respect to each other"

#### alancalverd

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##### Re: Is distance an absolute invariant?
« Reply #256 on: 11/02/2016 10:02:20 »
I thought Einstein had to make GR with maths to justify the fairy tale like SR?

The fairy tales are in your head, friend, but you are beginning to replace them with common sense and observation.

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #257 on: 11/02/2016 10:05:18 »
Space Flow, if you take on board my scenario of an observer on a railway station platform, standing on a gravity machine that is reducing the observers gravitational field by the inverse square law with each train carriage that is passing at a constant velocity,  this is why I said the observed reference frame is moving faster than the observers reference frame.

No matter, I'm getting the info I want, I think (chuckle)

Susskind lectures tell me (I think) that the Lorentz transformations are used to describe the effects of time dilation and distance contraction in relation to velocity for matter.

Susskind lectures tell me (I think) that the Lorentz transformations are also used to describe the stretching of the fabric of space.  Is this correct?

I think you just confirmed this, right?  (Scratches head...(chuckle))

I get exactly where you are coming from about the equivalence principle.

Yes, established physics states that gravitational time dilation is apparent in a gravitational field.  If the field decreases, the rate of time increases.  Just to check, it is not the Lorentz transformations that describes this gravitational time dilation?  Right?

I'm going somewhere with this, but let me first check that I'm correct so far please...

correction  -  If the field decreases, the rate of emittance of the caesium atom decreases.

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #258 on: 11/02/2016 10:07:01 »
I thought Einstein had to make GR with maths to justify the fairy tale like SR?

The fairy tales are in your head, friend, but you are beginning to replace them with common sense and observation.

I have no fairy tales in my head, I never had or have, it is not me who persists that the caesium atoms rate is time itself, and this is exactly what science is saying, you are all saying that the caesium rate is time itself, when I observe the caesium atom and its rate, I observe it is in time.

« Last Edit: 11/02/2016 10:09:35 by Thebox »

#### Space Flow

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##### Re: Is distance an absolute invariant?
« Reply #259 on: 11/02/2016 10:14:00 »
I have not once denied the results of the experiments, I am saying the results are not what you think they mean.  i.e the clock and clocks rate can not affect what it is measuring.
At least we are still in agreement. You see I understand that is what you are saying.
What I am asking is what "in the way you think things are", causes those experiments carried out multiple times by multiple different unconnected and dedicated experimenters with multiple different methods to all produce the same results. Results that are perfectly predicted by GR.
See I am not arguing with your statement that these results are not caused by what I think causes them. I am asking you to explain to me how you explain why they are so. What causes these professionally perfectly calibrated systems of measurement to all show the same differences in what they are measuring.
Don't keep saying what I think is wrong, show me a better reason for the observations, and convince me that what you say causes these results is closer to the truth than what others say.
This is your chance to prove to everyone that your stories are worth listening to.
The stage is yours. Dazzle us with your explanation of why the Universe is showing us these misleading data.

#### timey

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##### Re: Is distance an absolute invariant?
« Reply #260 on: 11/02/2016 10:21:41 »
What I do not understand is how come the Lorentz transformations form part of the GR field equations.  How are these concepts of special relativity and general relativity considerations being intertwined?

Because by definition GR must simplify to SR if there is no acceleration or gravitational field. SR is, as it says, a special case of R.

...and in the voids between galaxies there is no gravitational field.  This having been ascertained as being a verabatum via the ascertation of paralax distances in relation to a gravitational field reducing by the inverse square law, and the constancy of the speed of light.  Correct?

#### Space Flow

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##### Re: Is distance an absolute invariant?
« Reply #261 on: 11/02/2016 10:26:01 »
correction  -  If the field decreases, the rate of emittance of the caesium atom decreases.
Off topic but timey had it right. As you get further from a centre of gravity time runs faster.
Example; time runs faster on the surface of the moon than on the surface of the Earth. Lower gravity dilation.
The difference just as a back of envelope calculation is only about 1 in a billion, but it is there just the same.
That means that the surface of the Moon has aged about four and a half years more over the life of the solar system, But the effect would still be there.

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #262 on: 11/02/2016 10:28:53 »
correction  -  If the field decreases, the rate of emittance of the caesium atom decreases.
Off topic but timey had it right. As you get further from a centre of gravity time runs faster.
Example; time runs faster on the surface of the moon than on the surface of the Earth. Lower gravity dilation.
The difference just as a back of envelope calculation is only about 1 in a billion, but it is there just the same.
That means that the surface of the Moon has aged about four and a half years more over the life of the solar system, But the effect would still be there.

So you are insisting that the Caesium atom and the Caesium's atoms rate is time itself and controls the whole Universe?

You are saying the four dimensions of mass, XYZ and t is the interwoven single state and space-time does not exist?

You are saying space-time is the 5th n-dimensional quality?

And a time contraction is not off topic.
« Last Edit: 11/02/2016 10:33:36 by Thebox »

#### Space Flow

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##### Re: Is distance an absolute invariant?
« Reply #263 on: 11/02/2016 10:39:49 »
...and in the voids between galaxies there is no gravitational field.  This having been ascertained as being a verabatum via the ascertation of paralax distances in relation to a gravitational field reducing by the inverse square law, and the constancy of the speed of light.  Correct?
In theory, the gravitational effect of spacetime by matter never disappears. It just weakens by the inverse square law as you state, but at some level it still exists as you approach infinity.
Of course practically if there was such a thing as a completely empty Void and you somehow placed yourself in the middle of it, and also arranged you angular momentum so you were equidistant from all concentrations of matter surrounding this void you would by curved space interpretation be in almost totally flat spacetime and your clock rate would be running close to as fast as is possible.
Again that constitutes a very special case and reality complicates things a bit.
There is no such thing as a totally empty Void that we have been able to find.
Such may not exist.

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #264 on: 11/02/2016 10:45:49 »
...and in the voids between galaxies there is no gravitational field.  This having been ascertained as being a verabatum via the ascertation of paralax distances in relation to a gravitational field reducing by the inverse square law, and the constancy of the speed of light.  Correct?
In theory, the gravitational effect of spacetime by matter never disappears. It just weakens by the inverse square law as you state, but at some level it still exists as you approach infinity.
Of course practically if there was such a thing as a completely empty Void and you somehow placed yourself in the middle of it, and also arranged you angular momentum so you were equidistant from all concentrations of matter surrounding this void you would by curved space interpretation be in almost totally flat spacetime and your clock rate would be running close to as fast as is possible.
Again that constitutes a very special case and reality complicates things a bit.
There is no such thing as a totally empty Void that we have been able to find.
Such may not exist.

You can't find the empty void because there is already things filling it.   Remove the matter,EMR and CBMR from the Universe, what do you  have remaining?

Remove the outer galaxies the minimal universe is the milky way. Space would relatively contract.

« Last Edit: 11/02/2016 10:48:13 by Thebox »

#### Space Flow

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##### Re: Is distance an absolute invariant?
« Reply #265 on: 11/02/2016 10:48:26 »
So you are insisting that the Caesium atom and the Caesium's atoms rate is time itself and controls the whole Universe?

You are saying the four dimensions of mass, XYZ and t is the interwoven single state and space-time does not exist?

You are saying space-time is the 5th n-dimensional quality?

And a time contraction is not off topic.
No that appears to be what you are reading even though it is not what I am writing.
I have said none of those things.
I am not talking about Caesium or any clock.
Those are your words not mine.
I was talking about time. Not a measure of time, but time itself. Cause and effect.
And as far as what I mean by off topic, I am not a multitasker.
I was asking you a question that you appear to be avoiding answering. That is the topic in the discussion between you and me.
One step at a time mr Box.

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #266 on: 11/02/2016 10:52:49 »
So you are insisting that the Caesium atom and the Caesium's atoms rate is time itself and controls the whole Universe?

You are saying the four dimensions of mass, XYZ and t is the interwoven single state and space-time does not exist?

You are saying space-time is the 5th n-dimensional quality?

And a time contraction is not off topic.
No that appears to be what you are reading even though it is not what I am writing.
I have said none of those things.
I am not talking about Caesium or any clock.
Those are your words not mine.
I was talking about time. Not a measure of time, but time itself. Cause and effect.
And as far as what I mean by off topic, I am not a multitasker.
I was asking you a question that you appear to be avoiding answering. That is the topic in the discussion between you and me.
One step at a time mr Box.

Sorry for my impatience,  what is your next question.

#### Space Flow

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##### Re: Is distance an absolute invariant?
« Reply #267 on: 11/02/2016 11:10:09 »
Sorry for my impatience,  what is your next question.
I can not formulate a next question until my previous one is answered.
Quote from: Space Flow on Today at 10:41:45
Quote from: Thebox on Today at 10:19:28
I attribute the change of rate of the caesium atom being relative to motion relative to another body and bodies motion, and the cause of behaviour is the motion of accleration , an object at rest in a constant gravity inertial reference frame, i..e an object on earth Fn=a9.82m/s=N , this is constant, you are changing the constant of a9.82m/s to create an off-set

I would ask you to expand on that please. And in expanding that explanation reference the fact that the effect has been shown to be measurable with one clock stationary on the Ground floor of a building, with the other clock stationary on the top floor of the same building.

I have not heard of that fact, and that would affect my reasoning. If indeed two stationary clocks, in the same building , one on the ground floor and the second on a upper floor, and the effect is observed, then I can only conclude that difference is because gravity is weaker at a distance and the upper clock is experienced less strength.  However they both would experience the same constant of Newtons and Fn unless things weigh slightly less at altitude,

I am not sure, something to with calibration maybe.

Quote from: Thebox on Today at 10:54:21
I have not heard of that fact, and that would affect my reasoning. If indeed two stationary clocks, in the same building , one on the ground floor and the second on a upper floor, and the effect is observed, then I can only conclude that difference is because gravity is weaker at a distance and the upper clock is experienced less strength.  However they both would experience the same constant of Newtons and Fn unless things weigh slightly less at altitude,

I am not sure, something to with calibration maybe.
Well have a think about that, maybe do some research to convince yourself that I am talking real data and not making sh1t up, and then get back to me.

EDIT: It has nothing to do with bad calibration. The experiment is not a one off. It has been repeatedly confirmed by different researchers and exactly matches the result predicted by General relativity every single time.

#### alancalverd

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##### Re: Is distance an absolute invariant?
« Reply #268 on: 11/02/2016 11:21:19 »
it is not me who persists that the caesium atoms rate is time itself

Nor does anyone else. Time is the dimension that separates sequential events. Nothing more, nothing less, no other words. We measure time by various means, the best of which is the cesium clock.

A yardstick or a statute chain is not "length itself": it is the means by which we measure length in a nonaccelerating reference frame.

Don't accuse other people of talking nonsense until you have acquired the knowledge to distinguish it, and the humility to use their language correctly.

#### alancalverd

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##### Re: Is distance an absolute invariant?
« Reply #269 on: 11/02/2016 11:25:49 »
and in the voids between galaxies there is no gravitational field.
Not quite true. GM/r2 is never zero except at some very special, infinitesimal, evanescent, lagrange points where the field vectors of all galaxies cancel.

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #270 on: 11/02/2016 11:32:20 »
it is not me who persists that the caesium atoms rate is time itself

Nor does anyone else. Time is the dimension that separates sequential events. Nothing more, nothing less, no other words. We measure time by various means, the best of which is the cesium clock.

A yardstick or a statute chain is not "length itself": it is the means by which we measure length in a nonaccelerating reference frame.

Don't accuse other people of talking nonsense until you have acquired the knowledge to distinguish it, and the humility to use their language correctly.

You measure time by various means, so how do you conceive that the rate of the clock affects what you are measuring?

#### Space Flow

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##### Re: Is distance an absolute invariant?
« Reply #271 on: 11/02/2016 12:01:35 »
You measure time by various means, so how do you conceive that the rate of the clock affects what you are measuring?
Thebox please just stop it. You have repeatably been told by a large number of people that it is only you that claims that this is what everyone else is saying.
WE consistently write one thing and you consistently read another.
That is not good communication skills.

Now take out some paper and write 100 times;
"Nobody conceives that the rate of the clock affects what is being measured".

#### jeffreyH

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##### Re: Is distance an absolute invariant?
« Reply #272 on: 11/02/2016 13:14:19 »
Gravity is not defined by GR. Length contraction is a very tricky subject. More on this when I have time.

#### jeffreyH

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##### Re: Is distance an absolute invariant?
« Reply #273 on: 11/02/2016 13:32:20 »
https://en.wikipedia.org/wiki/Length_contraction
"Length contraction is the phenomenon of a decrease in length of an object as measured by an observer which is traveling at any non-zero velocity relative to the object."

Note decrease in length of an object and not spacetime. However an object in motion, normally it is stated as accelerating, will radiate gravitational waves which will in turn affect other objects in the vicinity. One does need to bear in mind that convention says it is only accelerating objects that radiate gravitational waves. Correct me if I am wrong.
« Last Edit: 11/02/2016 13:35:46 by jeffreyH »

#### Thebox

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##### Re: Is distance an absolute invariant?
« Reply #274 on: 11/02/2016 14:37:00 »
You measure time by various means, so how do you conceive that the rate of the clock affects what you are measuring?
Thebox please just stop it. You have repeatably been told by a large number of people that it is only you that claims that this is what everyone else is saying.
WE consistently write one thing and you consistently read another.
That is not good communication skills.

Now take out some paper and write 100 times;
"Nobody conceives that the rate of the clock affects what is being measured".

I will stop it when you stop calling it a time dilation.

#### The Naked Scientists Forum

##### Re: Is distance an absolute invariant?
« Reply #274 on: 11/02/2016 14:37:00 »