If SOL were infinite

[michel123456]

The cornerstone of Relativity is that Speed Of Light is finite.

What would be the description of a universe in which S.O.L. is infinite? In which way would be our observations transformed ?

[Mr Skeptic]

We'd need to redefine the meter (the meter would be infinite as currently it is based on the SoL). The special theory of relativity would probably look just like Newtonian mechanics.

[michel123456]

And we would see the galaxies as they are today.

Would we see the Big bang? since there would be no delay due to distance?

[Moontanman]

We'd need to redefine the meter (the meter would be infinite as currently it is based on the SoL). The special theory of relativity would probably look just like Newtonian mechanics.

 

Wouldn't be more accurate to say we couldn't use the speed of light as a measurement tool?

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Consecutive posts merged

And we would see the galaxies as they are today.

Would we see the Big bang? since there would be no delay due to distance?

 

We would see everything as it is today, the speed of light could no longer be used to see into the past so the big bang would be long gone in deep time.

[Sisyphus]

Would we see the Big bang? since there would be no delay due to distance?

 

It's the delay due to distance that lets us see the early universe. So no. What prevents us from "seeing the big bang" now is that the very early universe was opaque, so the end of that period is as far/early as we can see.

 

What it would mean is that we would have no limit to the distance we can see like we do now. There would be no "observable universe" in the sense we have now, no cosmological horizon. In theory we could see infinitely far, though not in practice, just because there would be stuff in the way.

 

The sky, I think, would look different, though I'm not quite sure how. Would distant objects still be redshifted? Would it be extremely bright? I'm not sure.

Edited December 16, 2009 by Sisyphus

[michel123456]

Right. (I mean I was wrong.)

It would be impossible to see anything from the past.

 

And what about Theory?

E=mc^2 ?

[Mr Skeptic]

There would be no redshifting (it would be infinitessimally small). A more serious problem with this consideration is that then we would need to rewrite the laws of physics (Maxwell's equations) and also what would happen to E=mc^2?

[michel123456]

A more serious problem with this consideration is that then we would need to rewrite the laws of physics (Maxwell's equations)

 

Why? I thought that laws of physics were independent of any specific value given for C.

[Mr Skeptic]

Maxwell's Equations are where the speed of light comes from. [math]c = \frac{1}{\sqrt{\mu_0 \epsilon_0}}[/math]. To get the speed of light infinite, one of these must be zero. I guess it would be [math]\mu_0[/math], and we have no more magnetism. I guess that wouldn't really be a problem. Except that without magnetism there would be no light...

[michel123456]

I am far from an expert in this field, but it seems to me a circular definition:

 

[math]

\epsilon_0 = \frac{1}{{\mu_0}{c_0^2}}

[/math]

 

where [math]

c_0

[/math] is speed of light in vacuum, as measured by experiment.

Edited December 18, 2009 by michel123456
Consecutive posts merged.

[Mr Skeptic]

That's the same equation, rearranged. Since we now have defined the meter based on the speed of light, it makes sense that we define another physical constant based off of it. But before all that, the speed of light was unknown.

 

In any case, even after rearranging the equation it doesn't change the fact that one of those will have to be zero with an infinite speed of light.