THE ESSENCE OF SPECIAL RELATIVITY

In the following video the observer starts moving with speed v away from the light source. One clearly sees that the speed of the wavecrests relative to him decreases (shifts from c to c'=c-v) and, accordingly, the frequency measured by the observer decreases as well (shifts from f=c/L to f'=(c-v)/L=f(1-v/c), where L is the wavelength):

http://www.youtube.com/watch?feature...&v=EVzUyE2oD1w
"General Relativity: Light in Gravity Fields"

Einsteinians also see that the speed of the wavecrests relative to the observer shifts from c to c'=c-v but then apply the fundamental calculation of special relativity:

c' = c - v = c

http://img15.hostingpics.net/pics/86...uletableau.jpg

Pentcho Valev