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SRH
2012-Nov-16, 12:59 AM
Mods: I'm not sure where else to put this thread...please move it if you think it should be moved.
This is more of a question rather than me defending an ATM theory. Thanks.
.....


If hypothetically, there were no such thing as space-time...rather, space was absolute in the third-dimension (i.e. there were no gravity wells),
then in what ways would light have to be different than our current conventions assume?

I imagine that C in a vacuum would no longer be constant,
and also that light would physically bend, changing directions in 3D.

Is this correct?
What else would be different?

John Mendenhall
2012-Nov-16, 01:30 AM
Mods: I'm not sure where else to put this thread...please move it if you think it should be moved.
This is more of a question rather than me defending an ATM theory. Thanks.
.....


If hypothetically, there were no such thing as space-time...rather, space was absolute in the third-dimension (i.e. there were no gravity wells),
then in what ways would light have to be different than our current conventions assume?

I imagine that C in a vacuum would no longer be constant,
and also that light would physically bend, changing directions in 3D.

Is this correct?
What else would be different?

Aside from the fact that space-time is demonstrably curved by massive objects so the question is rather meaningless, why do you think that c would not be constant?

SRH
2012-Nov-16, 03:36 AM
Aside from the fact that space-time is demonstrably curved by massive objects so the question is rather meaningless, why do you think that c would not be constant?

if speed = distance over time,

and "distance" assumptions are changed to a constant (warped space-time stretches out to a normal 3-D box/grid),
and "time" is changed to constant linear time,

then the speed of light would have to be variable in order to match observations, and it would also have to physically bend towards mass for a different reason than following the contours of space(-time).

Shaula
2012-Nov-16, 07:28 AM
Space was absolute in the third dimension? Space has 3 dimensions. Are you now saying that proper distances in the direction 'up' don't change? Well that can be proven wrong pretty fast.

Swift
2012-Nov-16, 02:27 PM
Mods: I'm not sure where else to put this thread...please move it if you think it should be moved.
This is more of a question rather than me defending an ATM theory. Thanks.

I've moved the thread from ATM to Q&A. Please make sure you keep it a question - if you start arguing against mainstream science (rather than asking questions about it) or advocate non-mainstream ideas, this thread will be closed.

Ken G
2012-Nov-16, 02:39 PM
It's a little unclear what you are asking, because we generally imagine that we do have access to spacetime regions that are free of gravity wells (or more correctly, free from important tidal influences from gravity wells)-- that's the spacetime that we do most of our routine small-scale calculations in! (Like the spacetime that CERN is using in their particle collision calculations, which to my knowledge include no GR and no effects of "gravity wells", yet still have constant c and all the usual trappings of special relativity). Bear in mind also that Einstein came up with special relativity, and the constancy of c, years before he came up with general relativity and the effects of gravity wells.

However, it is possible you are asking about "Mach's principle", which is the basic idea that the gravity from masses everywhere else accounts for the inertia of masses here. If one holds to that idea, which was a motivator for Einstein (but which is still debated if it is a true principle in GR), then one might imagine that even properties of locally flat spacetime (i.e., no important role for gravity) in some sense exist due to the gravitational history of the universe that gave rise to that piece of spacetime. If one takes that perspective, I don't think one can answer your question, it would basically mean that "all bets are off" if we can't include gravity, and we have no idea if spacetime could even exist at all, let alone what properties it would have.

So I would say the answer to your question is either, in the absence of gravity wells c would still be constant and special relativity would still apply locally, or, in the complete absence of any gravity, spacetime could be anything or not even exist at all-- depending on what you are asking about and on the unknown basis of why GR and SR hold.

John Jaksich
2012-Nov-16, 04:19 PM
Mods: I'm not sure where else to put this thread...please move it if you think it should be moved.
This is more of a question rather than me defending an ATM theory. Thanks.
.....


If hypothetically, there were no such thing as space-time...rather, space was absolute in the third-dimension (i.e. there were no gravity wells),
then in what ways would light have to be different than our current conventions assume?

I imagine that C in a vacuum would no longer be constant,
and also that light would physically bend, changing directions in 3D.

Is this correct?
What else would be different?

If I hear you correctly---it is as if you are saying *light --primarily obeys Newton's classical laws* and science does not have a grasp of what would be known as *Einstein's theory of Special Relativity*----rather there is some other "speed limit"?

It seems like a question of semantics---but I don't want to denigrate your question.

I suppose my answer would be: observe nature as you would in classical mechanics, exclusively.

grapes
2012-Nov-16, 05:49 PM
If hypothetically, there were no such thing as space-time...rather, space was absolute in the third-dimension (i.e. there were no gravity wells),
then in what ways would light have to be different than our current conventions assume?

I imagine that C in a vacuum would no longer be constant,
and also that light would physically bend, changing directions in 3D.

Is this correct?
What else would be different?


then the speed of light would have to be variable in order to match observations,
You're trying to do that, *and* match observations? That is impossible, unless you also throw out Newton's laws and Maxwell's, I'm pretty sure.