Re:What's Wrong With E=MC^2?
by Anon84 on Saturday August 15, 2009 @09:04PM
(#765437)
I am no physicist and would appreciate if somebody can explain why the speed of light is used everywhere in physics, specially in that E=mc2 formula.
This is a consequence of the invariance of the speed of light. You can pretty much derive Lorentz transformations (and a large chunk of special relativity) by simply forcing the speed of light to always be the same regardless of how fast you are moving with respect to the light source. (For a sketch see http://astro1.panet.utoledo.edu/~ljc/voigt02.jpg and http://en.wikipedia.org/wiki/Lorentz_transformation#From_phy... for a more detailed example).
A direct consequence of the form of the transformation factor \beta=1/(sqrt(1-(v/c)^2) is that you can't go over the speed of light without getting all sorts of imaginary (as in non physical) quantities.
This is a consequence of the invariance of the speed of light. You can pretty much derive Lorentz transformations (and a large chunk of special relativity) by simply forcing the speed of light to always be the same regardless of how fast you are moving with respect to the light source. (For a sketch see http://astro1.panet.utoledo.edu/~ljc/voigt02.jpg and http://en.wikipedia.org/wiki/Lorentz_transformation#From_phy... for a more detailed example).
A direct consequence of the form of the transformation factor \beta=1/(sqrt(1-(v/c)^2) is that you can't go over the speed of light without getting all sorts of imaginary (as in non physical) quantities.