https://www.youtube.com/watch?v=MHGxszX9WVc
Peter Galison: "He [Einstein] knew that the speed of light was something that was absolute."

How did Einstein know that? Actually he didn't - there was no evidence supporting the constancy of the speed of light (rather, any reliable evidence supported the variable speed of light predicted by Newton's emission theory of light). Einstein derived the false constancy from the Lorentz transforms, then called it "postulate" and finally, in his 1905 paper, derived the Lorentz transforms from the postulate (the gullible world was enraptured):

http://germanhistorydocs.ghi-dc.org/...in_ENGLISH.pdf
Albert Einstein, What Is The Theory Of Relativity? (November 28, 1919): "The second principle, on which the special theory of relativity rests, is the "principle of the constant velocity of light in vacuo." This principle asserts that light in vacuo always has a definite velocity of propagation (independent of the state of motion of the observer or of the source of the light). The confidence which physicists place in this principle springs from the successes achieved by the electrodynamics of Maxwell and Lorentz."

http://www.amazon.com/Introduction-S.../dp/048668895X
Introduction to Special Relativity, James H. Smith, p. 42: "We must emphasize that at the time Einstein proposed it [his second postulate], there was no direct experimental evidence whatever for the speed of light being independent of the speed of its source. He postulated it out of logical necessity."

The speed of light is not absolute - rather, both the frequency and the speed of light (relative to the observer) VARY with the speed of the observer, as the following videos clearly show:

http://www.youtube.com/watch?v=bg7O4rtlwEE
"Doppler effect - when an observer moves towards a stationary source. ...the velocity of the wave relative to the observer is faster than that when it is still."

http://www.youtube.com/watch?v=SC0Q6-xt-Xs
"Doppler effect - when an observer moves away from a stationary source. ....the velocity of the wave relative to the observer is slower than that when it is still."

Pentcho Valev