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Old 2009-11-11, 21:58   #1
Flatlander
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Default Changes to the speed of light.

Thinking out loud and more physics than maths, but I'm more comfortable here than at a physics forum.

What would the night sky look like if the speed of light (all electromagnetic radiation) was infinite?

1) Since the Big Bang
2) If it suddenly changed now.

What other consequences would there be?
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Old 2009-11-11, 23:04   #2
R.D. Silverman
 
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Quote:
Originally Posted by Flatlander View Post
Thinking out loud and more physics than maths, but I'm more comfortable here than at a physics forum.

What would the night sky look like if the speed of light (all electromagnetic radiation) was infinite?

1) Since the Big Bang
2) If it suddenly changed now.

What other consequences would there be?
Hint: E = MC^2; 'think solar fusion'
2nd hint: for particles with zero rest mass, E = h nu; nu = C/lambda.

Didn't you study any physics???
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Old 2009-11-11, 23:30   #3
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Quote:
Originally Posted by R.D. Silverman View Post
Hint: E = MC^2; 'think solar fusion'
2nd hint: for particles with zero rest mass, E = h nu; nu = C/lambda.
I think the intent of the OP was:
Suppose light traveled with infinite velocity instead of at Einstein's constant c.

So E = mc^2, not
E=\left\{<br />
\begin{array}{lr}<br />
0,&\;m=0\\<br />
\infty,&\;m>0<br />
\end{array}<br />
\right..
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Old 2009-11-11, 23:38   #4
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C'mon, Bob, live a little, let your hair down.

...and what are you doing in the homework help forum anyway?
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Old 2009-11-12, 00:04   #5
Flatlander
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I appreciate your hints Bob.
I studied very little physics but can see that plugging an infinite C into E=MC^2 might cause a few problems!

I will need to research the other hint and CRG's post.

I can see that my questions are more philosophical nonsense than science so I will dig myself deeper into the pit:

The Hubble Telescope version 31415 is built in 13bn years time and zooms in on the same area of sky that the Hubble Ultra Deep Field picture shows. What would it see?
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Old 2009-11-12, 00:30   #6
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Quote:
Originally Posted by Flatlander View Post
I appreciate your hints Bob.
I studied very little physics but can see that plugging an infinite C into E=MC^2 might cause a few problems!

I will need to research the other hint and CRG's post.

I can see that my questions are more philosophical nonsense than science so I will dig myself deeper into the pit:
.....
Err I will disagree; your questions are not nonsensical.
Physic laws are not necessarily as 'absolute' as mathematical laws(theorems) based on invariant axioms of systems.

I forget if it was Newscientist or one of the other 'fairly reputable' science reads on the internet mentioning that quite possibly some 'laws of physics' we here on Earth have arrived at may not actually hold throughout the entire universe. I believe it was the same article that also was making mention of various physics ruminations about constants and laws of physics for our universe being very 'special' and 'conducive' to life.[Yes, we are a living example of that aren't we. The point is that matter, planets or we wouldn't exist if some physical constants were minutely different.]

It may be that some laws (of physics) & equations have missing terms that we are yet to discover.
I just don't like the speed of light being a limiting factor! I yearn for the "Infinite Improbability Drive"!

Bob's answer about fusion was a good one :)
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Old 2009-11-12, 03:33   #7
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Quote:
Originally Posted by xkey View Post
Err I will disagree; your questions are not nonsensical.
Physic laws are not necessarily as 'absolute' as mathematical laws(theorems) based on invariant axioms of systems.

I forget if it was Newscientist or one of the other 'fairly reputable' science reads on the internet mentioning that quite possibly some 'laws of physics' we here on Earth have arrived at may not actually hold throughout the entire universe. I believe it was the same article that also was making mention of various physics ruminations about constants and laws of physics for our universe being very 'special' and 'conducive' to life.[Yes, we are a living example of that aren't we. The point is that matter, planets or we wouldn't exist if some physical constants were minutely different.]

It may be that some laws (of physics) & equations have missing terms that we are yet to discover.
I just don't like the speed of light being a limiting factor! I yearn for the "Infinite Improbability Drive"!

Bob's answer about fusion was a good one :)
Blah, cannot find where I read some newer related material this year which is what brought this to mind.

Did find a very interesting read http://www.salon.com/books/feature/2...ies/print.html

I liked the one theory I hadn't read before pulling in quantum physics and John Wheelers concept of a "participatory universe"; causality not only extending forward in time but also backwards -so that life in the universe managing to shape the original creation of the universe making it conducive to that future life which will arise.
It fits in nicely with uncertainty & doesn't require any external entity to be responsible for the creation of the universe.

If you do a search you'll end up finding a lot of pablum and nutjobs. I did find some useful summaries here http://www.absoluteastronomy.com/top...tuned_universe

Of course there are various theories that someday one can create one's very own universe - if/when that is true mine will contain 1) infinite beer 2) infinite pizza and steaks and 3) infinitely many stacked women and moi as the single male
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Old 2009-11-12, 06:30   #8
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anyone ever seen a snake start eating its own tail? and keep eating? when does it disappear?

c is not so much a speed limit as it is a measuring stick stuck in the corner of a room. one wall of the room is distance, the other is time. the further you move the stick up the distance wall, the further out the time wall it has to go and vice versa.

So if we presume that C were somehow a different value than it currently is, then quite a few fundamental constants would have to change and inherently the universe would have to be a much hotter place. I personally prefer the current "cool" universe.

DarJones
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Old 2009-11-12, 12:30   #9
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Quote:
Originally Posted by R.D. Silverman View Post
Hint: E = MC^2; 'think solar fusion'
2nd hint: for particles with zero rest mass, E = h nu; nu = C/lambda.

Didn't you study any physics???
I will try to give two alternative formulations of what I believe to be the intent of the OP while meeting Bob's objection.

Formulation 1: Professor Blindstein is a member of an intelligent technological society of organisms which possess only chemical and mechanical senses. That is, they have taste, smell, touch and hearing. He has a well-developed visual cortex with a rich imaging capability, the sensory input for which comes from active and passive sonar. Professor Blindstein used complex mathematical ideas to produce a physical theory which takes as its central tenet that the speed of sound is constant in a given material, though differs in different materials. This theory gives very good agreement with experiment. How would you explain to Professor Blindstein what his universe "looks" like?

Formulation 2: Physicists show that to an extremely high degree of precision that the strong, weak and electromagnetic interactions all propagate at the same fixed speed c, the so-called "speed of light in vacuum". They even have some evidence that gravitational radiation propagates at the same speed. One day, it is discovered that another form of interaction exists: the N-interaction. N-rays appear to travel at a speed much greater than the speed of light, so high that experimental results are consistent with it being infinite. A property of the N-interaction is that whenever an electromagnetic interaction produces a photon, the N-interaction produces an N-ray. A N-ray telescope is built. What does the universe look like when observed in N-rays?


I won't go much further, to allow others to contemplate these formulations, but I would suggest that it may be worth thinking about Olbers' paradox.


Paul

Last fiddled with by xilman on 2009-11-12 at 12:31 Reason: Fix minor typo
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Old 2009-11-12, 13:09   #10
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Perhaps we can consider the equivalence to quantum entanglement. So far all experimental evidence is consistent with infinite propagation speed.

An infinite speed of light (light as we currently understand it) would also allow instantaneous communication and the associated causality problems. So perhaps in a world where light travels at infinite speed we would find it impossible to communicate using light. Impossibility of communicating with light would also entail impossibility of controlling it. All light emissions would have to be random and unpredictable. Thus, there could be no stars, or any steady EM wave sources.
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Old 2009-11-12, 13:33   #11
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Quote:
Originally Posted by xilman View Post
Olbers' paradox
Doesn't luminous intensity drop off as the square of the distance? I mean, zeta(2) is finite...

Last fiddled with by CRGreathouse on 2009-11-12 at 13:35
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