# Basic Relativity Question

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Einstein said we are all traveling through the time dimension at C....can we feasibly say that one second equals to around 3 times $10^8$?

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1 second roughly equals 3*10^8 m / c, yes.

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1 second is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition (a change from one physical state to another) between the two hyperfine levels of the ground state of the cesium-133 atom.

The problem is that we don't know what time is. Once we find out what time, space, mass and energy really are, we can combine general relativity with quantum mechanics for a final theory.

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Einstein said we are all traveling through the time dimension at C....can we feasibly say that one second equals to around 3 times $10^8[/math']? Starting with this (Planck time) write this: [math] 1.35 \times 10^{-43} \frac{\text{seconds}}{\text{state change}}$

1) If the previous statement is true, then how many times does the universe change state per second?

2) What must be true for the above statement to be false?

The answer to question one is trivial, the answer to question 2 is not.

$\frac{1}{1.35 \times 10^{-43}} \frac{\text{state changes}}{\text{second}} = 7.4 \times 10^{42} \frac{\text{state changes}}{\text{second}}$

The previous number is enormous.

Suppose that you are in a reference frame, in which a photon has the following speed:

$c = 299792458 \frac{meters}{second}$

How many meters does the photon jump, in one state change?

$(1.35 \times 10^{-43}) (299792458) = 4.05 \times 10^{-35} \frac{\text{meters}}{\text{state change}}$

With a magnifying glass, the motion of the center of mass of the photon would look like this:

...............................................

The distance between any two points would be on the order of 10^-35th of a meter, and assuming the photon moves at a constant speed for the entire second, the distance between any two adjacent points would equal the distance between any other two adjacent points.

To another person, moving at a constant speed relative to the photon, the amount of distance the photon jumps would be different, but, in one second, it would have been at 7.4 x 10^42 different places.

So in different frames, the distance the photon jumps is different, but given that time flows equitably in all frames, the number of different positions occupied per second, would be the same in all frames, except ones in which the photon is at rest.

However, according to the theory of SR, time does not flow equitably in all frames.

The answer to question two is difficult to understand.

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I would think that, in order to take SR to its roots, you would have to give up the idea that we all move through some time dimension. That implies that there is some absolute time to be referenced. I don't even think Einstein could really talk about a time dimension. His idea of time, at least the one layed out in relativity, is based on the physical movements of a clock. He basically said that the OBSERVED rate of vibration in a frame moving relative to an observer will APPEAR slower to the observer. That's it. Nothing about moving through time, time travelling etc...

From his simple definition of physical vibration rates, this whole idea of actually moving through another dimension (time) at different rates was born.

If one accepts both spacial and time references (absolutes), you can achieve the same results (slowing of physical vibration based on velocity), while providing a real mechanism for the rate changes (lacking in relativity). That may be another discussion, but the idea would follow that for a high-speed frame (wrt absolute space) the rate of vibration internal to the frame would slow. Basically, it would take longer (wrt absolute time) for one vibration to occur. Once it slowed to absolute zero (wrt absolute space), fewer vibrations would have occurred on the previously moving clock than would have occurred on a stationary clock. Physical time would have slowed for that moving frame.

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I would think that, in order to take SR to its roots, you would have to give up the idea that we all move through some time dimension. That implies that there is some absolute time to be referenced.

Or you could take your direction of movement in spacetime and call it the time dimension (because in your frame of rest you only move in time direction).

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If one accepts both spacial and time references (absolutes)

But one has no basis for accepting this, seeing as it has been experimentally falsified.

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I know swansont, it has been experimentally verified that there is neither space nor time

There can be no physical (real) change in the rate of vibration for any physical object based soley on its velocity relative to some other (any other) observer. There simply is no mechanism by which it could be accomplished. It may be OBSERVED to be different from another reference frame, but basing actual physical changes on relative velocities, without a common baseline makes no sense.

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There can be no physical (real) change in the rate of vibration for any physical object based soley on its velocity relative to some other (any other) observer. There simply is no mechanism by which it could be accomplished. It may be OBSERVED to be different from another reference frame, but basing actual physical changes on relative velocities, without a common baseline makes no sense.

Makes no sense to you, perhaps. But argument from incredulity is hardly a compelling argument.

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Also, modern theories are based on frame-independent concepts like the Lagrangian Density (not sure if that helps you Saint, I didn´t understand your last post). In fact, frame-independace is usually considered a requirement for new theories.

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There can be no physical (real) change in the rate of vibration for any physical object based soley on its velocity relative to some other (any other) observer. There simply is no mechanism by which it could be accomplished.

Well...that's right! But it doesn't imply a frame of absolute rest.

The rate of vibration of a physical object doesn't become different in different frames. It simply is different in different frames. There is no mechanism necessary because nothing whatsoever is happening to the clock.

It may be OBSERVED to be different from another reference frame' date=' but basing actual physical changes on relative velocities, without a common baseline makes no sense.

Good thing SR doesn't do that then!

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Well...that's right! But it doesn't imply a frame of absolute rest.

Tom - what I'm saying is that, if there are actual changes in the rate of vibration, then there should be a common baseline. That would provide a mechanism.

The rate of vibration of a physical object doesn't become different in different frames. It simply is different in different frames. There is no mechanism necessary because nothing whatsoever is happening to the clock.

Well' date=' saying that something "just is", doesn't help much, Tom.

And what's is your take on the classis paradox? If one clock stays here on earth, and another takes a high-speed (close to c) trip around pluto and back, assuming they were in synch prior to the trip, would they be different after the trip?

If they would be different, I'd like to hear about the mechanism you have said is not needed. If their clocks are the same, then relativity really doesn't say much other than OBSERVING other moving frames can lead to different OBSERVED rates of vibration. Basically it has no physical value.

Good thing SR doesn't do that then!

Again, does SR have any connection to a physical reality? Or what exactly do you mean by that statement? Thanks for the response.

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Makes no sense to you, perhaps. But argument from incredulity is hardly a compelling argument.

Please tell me the mechanism that leads to physical changes in vibration rates based soley on a frame's velocity relative to anything else. Not the equation you would use to calculate it, but the actual mechanism.

I'll ask you the same paradox question that I asked Tom. In the twin paradox, does the returning twin's clock match the earth twin's clock once they meet back on earth?

And swansont, what are the experiments that have proven that absolute space does not exist? We may have proven that we haven't found it, but that's something else entirely.

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Please tell me the mechanism that leads to physical changes in vibration rates based soley on a frame's velocity relative to anything else. Not the equation you would use to calculate it' date=' but the actual mechanism.

I'll ask you the same paradox question that I asked Tom. In the twin paradox, does the returning twin's clock match the earth twin's clock once they meet back on earth?

And swansont, what are the experiments that have proven that absolute space does not exist? We may have proven that we haven't found it, but that's something else entirely.[/quote']

Could you tell me why walking away from something makes it physically smaller?

What is the actual mechanism?

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Could you tell me why walking away from something makes it physically smaller?

What is the actual mechanism?

Walking away from something doesn't make it smaller.

Walking away from something makes it appear to your eye to be smaller.

This is because what you see are photons, which left the object. You don't see the object, you see photons.

You can draw a picture to help you understand, a ray diagram.

You draw lines into your eyeballs.

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Please tell me the mechanism that leads to physical changes in vibration rates based soley on a frame's velocity relative to anything else. Not the equation you would use to calculate it' date=' but the actual mechanism.

I'll ask you the same paradox question that I asked Tom. In the twin paradox, does the returning twin's clock match the earth twin's clock once they meet back on earth?

And swansont, what are the experiments that have proven that absolute space does not exist? We may have proven that we haven't found it, but that's something else entirely.[/quote']

The constant speed of light in inertial reference frames cause measurements to be different in each frame.

The twin that undergoes an acceleration has changed frames, so the clocks will not match up.

The Michelson-Morley experiment showed that we are not moving through a preferred frame. Stellar aberration showed we are not at rest in a preferred frame.

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Stellar aberration showed we are not at rest in a preferred frame.

Dr Swanson, can you explain stellar aberration to me, I just read about it somewhere else, and I didn't know what it is.

If it's really complicated, don't bother.

Kind regards

PS: Actually, I'll do the work on my own, so nevermind. Just ignore the question.

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Dr Swanson' date=' can you explain stellar aberration to me, I just read about it somewhere else, and I didn't know what it is.

If it's really complicated, don't bother.

Kind regards

PS: Actually, I'll do the work on my own, so nevermind. Just ignore the question.[/quote']

What was the point of posting this, if the conclusion is to ignore it? There's no indication that the PS was edited in later.

But it's good that you look this up on your own. It's a simple Google search.

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Walking away from something doesn't make it smaller.

Walking away from something makes it appear to your eye to be smaller.

This is because what you see are photons' date=' which left the object. You don't see the object, you see photons.

You can draw a picture to help you understand, a ray diagram.

You draw lines into your eyeballs.[/quote']

I guess I'm a little slow. Most people pick up on this sometime in their first year of life.

I guess the point I was trying to make was that you generally don't effect a physical change to something remote by changing your frame of reference, or by your velocity in a frame of reference. Your conclusions about the physical state of something may change but those "perspectives" already existed or were poised to exist anyway (I would say simultaneously but that would be a poor choice of wording relatively speaking)

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Tom - what I'm saying is that' date=' if there are actual changes in the rate of vibration, then there should be a common baseline. That would provide a mechanism.

[/quote']

And I'm saying that there aren't any actual changes.

Well, saying that something "just is", doesn't help much, Tom.

The universe isn't known a priori. It is the nature of scientific reductionism to explain things in terms of other, unexplained things.

And what's is your take on the classis paradox? If one clock stays here on earth, and another takes a high-speed (close to c) trip around pluto and back, assuming they were in synch prior to the trip, would they be different after the trip?

There is no paradox. A paradox occurs when, for some statement X, it is possible to derive both X and ~X from a theory. With SR, it is not possible to do that for any statement X.

If they would be different, I'd like to hear about the mechanism you have said is not needed.

They are different, but why would I tell you about a mechanism that I do not even believe exists, or see a need for?

If their clocks are the same, then relativity really doesn't say much other than OBSERVING other moving frames can lead to different OBSERVED rates of vibration. Basically it has no physical value.

Moot point, because they are different.

Again, does SR have any connection to a physical reality? Or what exactly do you mean by that statement? Thanks for the response.

Yes, SR does have a connection to physical reality. Its postulates have been experimentally verified, and the consequences of those postulates describe spacetime locally very well.

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There is no paradox. A paradox occurs when, for some statement X, it is possible to derive both X and ~X from a theory. With SR, it is not possible to do that for any[/b'] statement X.

How about the paradox that any frame can claim that every other frame is vibrating at a slower rate?

And I'm saying that there aren't any actual changes....

They are different' date=' but why would I tell you about a mechanism that I do not even believe exists, or see a need for?[/quote']

How do these two statements coincide? First you say that there aren't any actual changes, then you say that the clocks will be different (actual change). I'm a little confused concerning this response.

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How do these two statements coincide? First you say that there aren't any actual changes, then you say that the clocks will be different (actual change). I'm a little confused concerning this response.

Nothing happens to the clock. What is different is the measurement of the clock.

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How about the paradox that any frame can claim that every other frame is vibrating at a slower rate?

It isn't a paradox. Work it out for yourself: Pick a statement and try to derive both it and its negation from the postulates of SR. You won't be able to do it.

How do these two statements coincide? First you say that there aren't any actual changes' date=' then you say that the clocks will be different (actual change). I'm a little confused concerning this response.[/quote']

The measurements are different, but nothing whatsoever happens to the clock. The clock is not altered in any way by the fact that other bodies are in motion relative to it.

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If two objects are not moving and percieve another object from different positions/perspections, are they relevent to each other?

pljames

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