What is the significance of VSL Theory in modern physics?

risendemon
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I'm not sure if I'm posting this thread in the correct category, but I figured i'd give it a shot. If this is posted in the wrong category, i apologise. Some of you are probably familliar with the variable speed of light theory. It's something I just recently stumbled upon, almost by accident. From what I can gather, it challenges inflation theory, the general theory of relativity, and yet debate about it is still within the realm of mainstream physics.

I am a physics minor and most of the details of VSL are a bit over my head, but I was wondering if I could hear what some more learned physicists think about it.

thanks a bunch,
Christoph
 
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While you're waiting to see if anyone else responds (I don't know anything about VSL theories myself), you can search for previous discussions. PF's own search function doesn't work very well, but you can use Google to search old discussions here by including "site:physicsforums.com" in the search string.

Here's what I get when I search for "VSL site:physicsforums.com":

http://www.google.com/search?q=VSL+site:physicsforums.com
 
Hi, risendemon,

Variable speed of light theories are actually a very old idea; the VSL proposal of Joao Magueijo is only the most recent contender. Older versions ran into various problems, which are discussed in many review papers on problems in cosmology. Magueijo's proposal was received with considerable interest some years ago http://arxiv.org/find/grp_physics/1/AND+abs:+Magueijo+abs:+AND+light+AND+speed+of/0/1/0/all/0/1
but I haven't been following its fortunes of late.

While searching unsuccessfully for a recent review paper for you, I found http://www.answersingenesis.org/docs2002/0809_cdk_davies.asp, from a "Creation Science" [sic] website which is apparently maintained by M. and T. Garoutte in KY. The Garouttes incorreclty claim "General Relativity has had a variable speed of light ever since 1917". This misstatement confuses coordinate speeds with velocities. VSL theories maintain that the physical speed of light varies--- gtr is not a VSL theory! The wider point here is: be careful of what you read on the internet. Not every page you find which claims to describe "science" would be recognized as such by scientists, and "Creation Science" [sic] websites are notoriously (sometimes hilariously) wrong about what gtr says (sometimes even what Galileo said!--- the website of Robert Sungenis http://en.wikipedia.org/wiki/Robert_Sungenis claims, not just that Einstein was wrong, but even that Kepler was wrong!)
 
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Chris Hillman said:
Hi, risendemon,

Variable speed of light theories are actually a very old idea; the VSL proposal of Joao Magueijo is only the most recent contender. Older versions ran into various problems, which are discussed in many review papers on problems in cosmology. Magueijo's proposal was received with considerable interest some years ago http://arxiv.org/find/grp_physics/1/AND+abs:+Magueijo+abs:+AND+light+AND+speed+of/0/1/0/all/0/1
but I haven't been following its fortunes of late.

While searching unsuccessfully for a recent review paper for you, I found http://www.answersingenesis.org/docs2002/0809_cdk_davies.asp, from a "Creation Science" [sic] website which is apparently maintained by M. and T. Garoutte in KY. The Garouttes incorreclty claim "General Relativity has had a variable speed of light ever since 1917". This misstatement confuses coordinate speeds with velocities. VSL theories maintain that the physical speed of light varies--- gtr is not a VSL theory! The wider point here is: be careful of what you read on the internet. Not every page you find which claims to describe "science" would be recognized as such by scientists, and "Creation Science" [sic] websites are notoriously (sometimes hilariously) wrong about what gtr says (sometimes even what Galileo said!--- the website of Robert Sungenis http://en.wikipedia.org/wiki/Robert_Sungenis claims, not just that Einstein was wrong, but even that Kepler was wrong!)

Being a geology major, i understand very well how errent creation 'science' can be. I've actually done many rebuttals of the so called 'c decay' they seem to talk about so much. This was actually how i came to find out about modern VSL theories, and why I wanted to ask some people with more physics knowledge than I have about it

thanks for the info!

---
Christoph
 
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jtbell said:
While you're waiting to see if anyone else responds (I don't know anything about VSL theories myself), you can search for previous discussions. PF's own search function doesn't work very well, but you can use Google to search old discussions here by including "site:physicsforums.com" in the search string.

Here's what I get when I search for "VSL site:physicsforums.com":

http://www.google.com/search?q=VSL+site:physicsforums.com

thanks a bunch for that, i didn't know google had that feature!
 
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