i read a article about some brazilian physicist who has a theory that says einstein is wrong. in this article he pretty much says that when the big bang occured , initially the speed of light was much faster than it is now.in addition after the universe "settled" thats when light became a constant. so is this true?
Posted: Tue Aug 11, 2009 5:46 pm
Please provide a bit more context. I don't know who you mean or what they said about it. I can assume that you meant Magueijo, but he is not Brazilian.
Talking about a change in the speed of light intrinsically is meaningless; the only way to make sense of it is to talk about some dimensional ratio, such as the fine structure constant or even just the ratio of speeds of electromagnetic and gravitational waves. In that sense we can talk about it, but we need something concrete and a mechanism.
There really doesn't seem to be any such mechanism behind Magueijo's theory. Since its competitor, inflation, actually does have both theoretical (as an outgrowth of the standard model and GTR) and evidential support, it loses. If I'm right in guessing which theory you're referring to, then it's not an exaggeration to say that it's at best borderline crackpot: it gives little while destroying much.