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Author Topic: An essay in futility, too long to read :)  (Read 279457 times)

Offline yor_on

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An essay in futility, too long to read :)
« Reply #125 on: 19/12/2010 04:57:58 »
So what the he* makes it possible. The energy expended? Well, that was the one I really liked and now when uniform motion doesn't matter? Except when matter, ahem :) we're back in play, ain't we.

Yep eeeneeergy.
==

There is one weird effect of it though, validating an idea I've had. For a long time I've assumed a photons 'timelessness' to be related to its 'masslessness'. I've seen other state that it have to do with its speed, don't think so friend:)

Masslessness rule :)

« Last Edit: 19/12/2010 05:05:07 by yor_on »
 

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An essay in futility, too long to read :)
« Reply #126 on: 19/12/2010 05:17:51 »
So let us consider a free fall towards a planet. Before I said I could accept the equivalence between matter and 'energy', calling a planet condensed 'energy'. Could I use that for redefining why the in-falling object will observe a time dilation and Lorentz contraction?

After all, think of it. The free falling object does not expend any energy, does it? But it's trucking along towards a object 'filled to the brim' with, ahem, frozen energy :) As that is what it is if we compare it to the state it was in, at the Big Bang. Our whole universe have to be in a 'frozen state' comparatively to that.
===

And inertia?

In a 'frozen universe', what could inertia be?
That remarkable 'resistance' to change?

And gravity?
« Last Edit: 19/12/2010 05:38:18 by yor_on »
 

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An essay in futility, too long to read :)
« Reply #127 on: 19/12/2010 06:19:05 »
Just a footnote:
 
I'm still not sure that uniform motion plays no part for time dilation and Lorentz contraction. But for the sake of arguing (as well as I can't see how to refute my own logic, dam*:) I will argue like I'm convinced, unless someone present definite proof of the opposite?

If you have and can resurrect my former belief I'm interested, not that it won't work this way too, but it becomes a universe in where 'motion' suddenly have a 'duality' and .. ?
« Last Edit: 19/12/2010 06:23:58 by yor_on »
 

Offline yor_on

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An essay in futility, too long to read :)
« Reply #128 on: 19/12/2010 07:28:39 »
Nope, I'll have to refute that one. It can't be right.

But when it comes to the muon free falling it is right that he will have a changed 'room time geometry' aka an equivalence to acceleration. and that screws up my beautiful geodesics, again :)

Let's see.

How to prove that uniform motion will have a time dilation :)

The first evidence is the evident absurdity the other idea introduces, especially if you think that the room time geometry will change in a acceleration.

The other is how to think about it. We have two theories of relativity, one called special relativity (SR) the other called general relativity (GR).

SR treats inertial frames (constant velocity without forces)
GR treats acceleration and gravity.

==

How do we know who introduced a change?
Think of it as a coordinate space.

You have A and B placed in different locations. If you are C you can see who moves first relative you. But when it comes to A and B then? That's where the acceleration comes in, to create a change you will need a acceleration, and the one introducing it ('A') will feel it as his inertia gets disturbed.

That's the simple one and falls under GR
 
=

But in a coordinate space where both are moving uniformly relative each other then?

There you will find it harder. First of all you can't really say who is moving relative one. It's a relative question who is moving relative who in this case. You can as easily define yourself as unmoving as the one you meet, or split the velocity into two or any mix inbetween, as I understands it. And this one falls under SR.

So how do we know that clocks slow down here too?
« Last Edit: 19/12/2010 07:53:34 by yor_on »
 

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An essay in futility, too long to read :)
« Reply #129 on: 19/12/2010 07:59:52 »
Think of two mirrors at rest relative yourself, then let a light-corn bounce between them. As it does you will find the path that light-corn to take being a straight path, back and forth.

Now let the mirrors move, it won't matter when you look at them, under the acceleration or after it. From your point of view the light-corn suddenly will move slower, due to you finding it having a longer path between the mirrors, as they constantly moves away from you. Also you will find the path to move in a diagonal as it 'tags' after the mirrors in a zigzag motion, relative you, being still.
==

You being still falls under SR but the mirror when accelerating falls under GR,and so as a 'system' you both belong to GR there. After the acceleration when it just 'coasts' you will both belong to SR.
==

But thinking of it, can you under any of those circumstances find a moment when that light-corn didn't move in zigzag, having a longer path to traverse between the mirrors?
==

Now imagine that you would move with those mirrors, being at a constant rest with them.
First of all, when will you be able to prove that you are moving?

The acceleration right?

How do you think that light-corn will behave then?
Will it zigzag according to you being at rest with the mirrors :)

Contrast that to when you've stopped accelerating, uniformly moving.
Will the light-corn zigzag?

Do you think there is a difference between the acceleration and later uniform motion?
==

For the last one, imagine each one of the above. The only difference being that you both are inside a very large box. It's really, really black in there as the engineers forgot all about the windows. So, in which scenario will you be able to say that you are 'moving'?
==

When you've done those, you will know what I think I know :)
And you're right, the mirrors becomes the light clock.
« Last Edit: 19/12/2010 08:43:20 by yor_on »
 

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« Reply #130 on: 19/12/2010 08:32:07 »
Hey, doesn't that destroy the equivalence I was talking about before between all 'uniformly moving' frames of reference? Nope, not when you do it in a black box scenario. And if we apply that on our muon free falling the geodesic he follows will be the same as if in deep space, as long as we ignore 'twisting' like the Coriolis force and 'frame dragging'.

So I change my mind, again :)

But doesn't the muon create a twisted 'room geometry' by himself then?
Yes, but if you exchange him for you, being inside a black box, free falling. How can you tell your possible 'speed'?

You can't.

How can you tell you're falling towards Earth?
No use trying that scale, it won't work.

Ignoring Coriolis force (and other frame dragging)
You can't.
==

Now imagine two sets of mirrors A and B passing each other in space, coasting or not.
How will their 'light-corns' tick? (Imagine yourself to be A first and look at B, then change)

And that's why it's nice with fixed stars, so far away that they 'never moves' relative Earth.
Helps you know when you're moving :)
« Last Edit: 19/12/2010 08:44:57 by yor_on »
 

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« Reply #131 on: 19/12/2010 10:58:21 »
So what did you see when jumping between those 'light clocks'. and was it real? I consider it 'real' but there are different interpretations to that. If we take the last example we can start with saying that we are on A and then meet B. Well knowing that A have a velocity relative an inertial frame like Earth I can then look at B:s light clock and divide part of that 'ticking' to get what will be his 'correct' velocity, relative Earth :) Earth as that is from where I got my initial idea of what for me is considered my 'rest frame'. So in a way i can just let the ticking be what it is and so get any velocity I like it seems, between null and the maximum speed his clock can describe. It all falls back to that there is no ''exact time device' in the universe. But how the he* will I know if I've reached my correct near light-speed then, if I can change my velocity just by changing reference frame?
 

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« Reply #132 on: 19/12/2010 11:01:44 »
If we had an aether we would have had a tarmac for our wheels to count their speed. but we have no such 'tarmac'. But we do have relativistic effects. And those are SpaceTimes answer to you speed/velocity, and only yours.
==

But to get back to the ordinary light clock. Yes, the ticking you see is 'real' but relative. Relative Earth, or Alpha Centauri or ... It is the 'right time' you see, you just don't know for whom, or if it needs to be 'split'. A weird subject indeed.
==

But if you think of it in form of your own unique 'room time geometry' it becomes easier to handle. You just need to remember that with acceleration and velocity that room will shrink, and so create your 'time dilation' and 'Lorentz contraction'. Then you can use relativistic effects to define your speed, if you don't have a defined 'rest frame'. It all builds on you knowing what to expect in form of hard radiation and 'Space Wrapping', aka the 'screen' you will meet at 'relativistic velocity' of course. But, it opens for surprising interpretations when it comes to what a uniform motion should be seen as, at least it does for me :)
« Last Edit: 19/12/2010 11:38:41 by yor_on »
 

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« Reply #133 on: 19/12/2010 12:04:25 »
It's been my impression that most mathematicians and physicists don't really want to discuss what those dilations and contractions 'is'. but a easy argument is to use 'room time geometry', and then say that in traveling near light speed the pilot will observe his SpaceTime contracted, as well as 'warped'. If we then assume that his meter stick still measures a meter for him and his heart beats the same according to his wristwatch. Then what is this contraction. Not real? Go tell him :)

I don't see how one can get past that fact. That this only comes to bear at very high velocities is no hindrance to the concept existing. And if it exist 'for real' then we have a very weird SpaceTime'
« Last Edit: 19/12/2010 12:38:32 by yor_on »
 

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« Reply #134 on: 19/12/2010 12:29:14 »
You might have noticed that I didn't use 'inertial rest frame' for Earth. that's because its a matter of interpretation with three :) answers

1.No. Earth rotates and have 'fictitious forces' like the Coriolis force.

2. Yes. In a Newtonian sense Earth is a 'inertial frame' in which Newton's laws of motion and the idea of inertia holds, having a constant velocity.

3.Yes. "Earth rotates around its axis as also revolves around the sun. In both these motion. Centripetal acceleration is present. Therefore, strictly speaking earth or any frame of reference fixed on earth cannot be taken as an inertial fame. However, as we are dealing with speeds  x 108 ms-1 (speed of light) and speed of earth is only about 3 x 104  m/s, therefore when small time intervals are involved effect of rotation and revolution of earth can be ignored. Furthermore, this speed of earth can be assumed to be constant. Hence earth or any other frame of reference set up on earth can be taken as an approximately inertial fame of reference."

And that last one I think most people use today, At least I do it :).

Einstein's famous though experiment about the elevator builds on treating Earth as a inertial frame of reference. Without that concept the general relativity's 'principle of equivalence' wouldn't exist. It states that a gravitational field at a uniform velocity is indistinguishable from a uniform acceleration in the opposite direction. And when we discussed the twin experiment there comes a 'time' when the traveling twin turns around to go back.

At that point it is as correct to see the Earthly twin as being the one falling down a gravity well with the 'traveling twin' being at rest and where the Earth twin 'age difference' being the result of 'turn-around acceleration'. That one is quite weird to me I must admit, and I'm not sure I really see how they think there? But I believe it to build on Einsteins idea that you could treat an 'accelerating reference frame' as it would 'create' a pseudo-force opposing the true acceleration of the reference frame? Or maybe not, it depends on where they expect it to happen? It's another weird one :) One could understand it as a centripetal force accelerating the rocket, maybe? But then it seems to me that this acceleration would have to be quite strong to produce such an effect? Heh.

Does that one even make sense :)
« Last Edit: 19/12/2010 13:40:32 by yor_on »
 

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« Reply #135 on: 19/12/2010 13:48:05 »
Ah :) Now it make sense, the only thing being that it haven't anything to do with the 'turn around' in itself..

"
The simplest way, if the duration of the acceleration is small, is to just divide the distance (according to each twin) by the relative velocity. Then double the results to get the answer for a two way trip.

For example, if a ship travels to a star 10 light yrs away from earth at 0.8c, the elapsed time on earth will be 10ly/0.8c= 12.5 yrs. And the elapsed time on the ship will be 6ly/0.8c= 7.5 yrs (the distance is 6 ly in the ship's frame due to length contraction).

So the difference in elapsed time (between earth departure and star arrival) between the twins for a one way trip is 5 yrs. For a two way trip, it's 10 yrs.

The asymmetry in this "resolution" is the simple fact that the distance between the earth and the turnaround point is defined in earth's frame (un-contracted) and contracted in the ship's (inertial) frame. The distance "expands" back from 6 ly to 10 ly in the ship's accelerated frame during the deceleration."

It's about having the turnaround defined from different frames. Kind of weird but I presume they have a reason? I like my 'room time geometries' better. Why mix it?
 

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« Reply #136 on: 20/12/2010 15:55:18 »
Now let us take a look at that light-corn again. As far as I understand this idea is the perfectly true one, but it's also remarkably weird. It catches the idea of 'frames of reference' perfectly, but if you think of it also says that there are no 'events' to it.

That it (time dilation and Lorenz contraction) grows with speed or velocity doesn't prove that it won't exist at lover speeds and velocities. And that we don't recognize it on Earth doesn't tell us a thing about if it's there or not. As all other proofs I can easily tell you that the reason why we don't perceive it at 'human standards' or biological is just the same reason why we 'work' and can 'communicate' in the linear human/biological way we do.
« Last Edit: 20/12/2010 16:54:14 by yor_on »
 

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« Reply #137 on: 20/12/2010 16:34:55 »
So, how about it?
Do we live in a 'frozen' 'SpaceTime'? And if we do, what have that to do with 'frames of reference'? It's just a way of looking at it but you could imagine a plasma and ask yourself how many 'frames of reference' there would be in one homogenized plasma. If we assume that it from an outside observer would have a very slow 'time frame'. What would it look like from the 'inside' from its own 'frame of reference' aka room time geometry.

Imagine a 'plasma', and that you're piloting it. Imagine it extremely hot and energetic, then, would you agree to this being the same as it having reached a 'relativistic speed' near what motion would take you being near light speed in a vacuum?

It actually doesn't have to 'move' relative 'something else' for reaching this state. Heat is 'energy', and expending 'energy' can be seen as both a 'Lorentz contraction' and a 'time dilation', but you could also assume that it was a very weird type of 'confined plasma' with all its processes directed in one direction, creating a 'thrust' inside our 'SpaceTime' to see my meaning. It's not needed but it's a 'equivalence' sort of. Because I'm coming to a slightly different question soon.
 

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« Reply #138 on: 20/12/2010 16:38:34 »
If that plasma created this time dilation and Lorentz contraction that I expect it able too, what would you see as its pilot? Would you see a 'Lorentz contraction'. If you think you would, is there a state where this plasma, or whatever you would like to call it. Is there a 'place' when it would become what we call a 'point particle'?
 

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« Reply #139 on: 20/12/2010 16:46:51 »
Remember how I discussed the 'energy' and Black holes? I said

"Or that I'm wrong in assuming that following a geodesic, free-fall, having no weight (if you tried to put a scale under your feet in that 'free fall' it wouldn't register you, so to speak:) towards Earth is the same as following any other geodesic?

But if it so, then I need someone to tell me where the difference lies?
That is, how to measure it?

But it has to be right, as the time dilation I would expect, falling into a Black Hole, from an outside observer, will be greater than if I was falling towards the Earth. Or proper mass doesn't create a time dilation..

And that one we know it does."

So, what was wrong with this assumption?

As I see it it was me forgetting my own idea of 'room time geometries'. There are two things twisting a 'room time geometry', proper mass and expending energy. Motion is a function of expending energy but a planet isn't 'expending' anything. But both ideas will twist your 'reality'.
 

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« Reply #140 on: 20/12/2010 17:01:53 »
So energy can contract a distance as seen from the inside of it?
Maybe, we wouldn't notice it (outside of it) if so, would we?

But if it was right there should be a time dilation to it, as measured from our 'frame of reference', shouldn't it? so maybe not? But I will continue assume that I'm right for a while :)
 

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« Reply #141 on: 20/12/2010 17:10:08 »
There was actually quite another question that this was leading too, but believe me or not, I've forgotten it :) but we can look at another one that also will work. If we assume a 'time dilation' to energetic processes, no matter if they are 'moving' in a vector or not, why don't we notice it here and now? Is the energies to 'weak' normally? Yep, that's what I think anyway :) Consider the experiments at CERN and the energies they expect themselves to need. But you might look at it differently?
 

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« Reply #142 on: 20/12/2010 17:18:35 »
And that takes us to the photon in a roundabout way. If energy can contract its 'distance' as defined from its own frame of reference, can it become a 'point particle'?

That's interesting, isn't it?
 

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« Reply #143 on: 20/12/2010 17:24:35 »
And that is another way of asking what it was I was thinking of originally.

Remember that I discussed the notion that you in your moving 'frame of reference' always would measure your 'distance' and 'arrow of time' as unchanging. No matter if you measure it on Earth, falling towards a 'Black Hole' or speeding away at some velocity as defined from 'somewhere else'.

Well, think of my question above and then tell me how to reformulate it so that we can in-cooperate both view points into one. As they are two 'points of views' inside the same 'frame of reference', at least when it comes to matter. Inside that ship my universe becomes really 'short' at the same time as my 'yard-stick' still measures a yard.

Heh, it became better, the question, as I forgot it?
The universe works in mysterious ways.
« Last Edit: 20/12/2010 17:45:29 by yor_on »
 

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« Reply #144 on: 20/12/2010 17:55:07 »
So is 'the arrow of time' a function of geometry? If we look at the 'mirror example' above we find that the reason for 'time slowing down' actually could be seen as a result of that light-corn having to 'traverse' a larger amount of 'space' as seen from us on Earth. But why doesn't he traveling on the mirror notice that too? Well, put that 'black room' around you both, then look down at that light-corn bouncing. Does it take a straight path or not?

If you imagine that it doesn't, then I can imagine a 'time when it stops 'ticking', as it will miss the oposite mirror totally, not reaching it in 'time'. And if that mirror-set with the light-corn bouncing could be seen as a 'clock', which it definitely is, then you have just introduced the concept of time stopping.
 

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« Reply #145 on: 20/12/2010 18:00:00 »
So, here's the next question. Looking at it, assuming that the concept of mirror-clock is correct. What is 'space', that classical 'nothing'. I say that it is a emergence from the 'rules' governing 'SpaceTime'. But can you think of some other way to explain it?
 

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« Reply #146 on: 20/12/2010 18:37:57 »
Think of that path you see the light-corn take from Earth. From your view, incorporating the 'arrow of time' the guy traveling experiences as being his 'normal' (from his point of view). From your view, or better still, with the eyes of a God :) Could we say that this guy is right, distances have actually become compressed, inside each 'tick' of that clock.

Now think of it, suddenly I left the question of 'motion', instead jumping to that single 'tick', stating it as possible to see as if each of those 'ticks' had a greater volume of 'space' compressed inside it.
 

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« Reply #147 on: 20/12/2010 18:56:34 »
So, what is it that makes it possible for us to discuss argue, and get downright ** at each other? Those 'ticks' I would say. How else can you think? Everything we do take some 'time'. You have nothing else to replace it with. Entropy doesn't discuss that creates thoughts, time does.
 

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« Reply #148 on: 20/12/2010 19:05:25 »
Or turn it around, do thoughts have an entropy?

Sure they do, they can stop, grow, die out, even reverse sort of. But, they do it inside an single 'arrow of time', pointing in one temporal direction.

From your birth to your death.
 

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« Reply #149 on: 20/12/2010 19:15:34 »
And if we go back to "Now think of it, suddenly I left the question of 'motion', instead jumping to that single 'tick', stating it as possible to see as if each of those 'ticks' had a greater volume of 'space' compressed inside it."

How does such a notion fit the idea of singular dimensions 'criss crossing' each other in every 'point' of SpaceTime?

I would say, badly.

I prefer the notion of 'properties'. Then what we see, in its 'internal workings', is a function of 'properties' undividable in Space. Just as a 'photons' properties. And then people can stop using one of the most irritating expressions I know :) Two-dimensional systems. In mathematics it's a useful tool, but when using it to describe a three-dimensional system I find it highly inappropriate.
« Last Edit: 20/12/2010 19:17:05 by yor_on »
 

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