In Doppler effect, the speed of light is OBVIOUSLY VARIABLE:
Stationary light source, moving receiver:
http://www.einstein-online.info/imag...ector_blue.gif
The speed of the light pulses as measured by the source is
c = df
where d is the distance between the pulses and f is the frequency measured by the source. The speed of the pulses as measured by the receiver is
c' = df' = c+v
where f'=c'/d=(c+v)/d is the frequency measured by the receiver, and v is the speed of the receiver relative to the source.
Einsteinians do admit that the frequency measured by the receiver is f'=c'/d, but don't admit that the speed of the pulses as measured by the receiver is c'=df'. They believe in the formula c'=c, for the following reason:
Ignatius of Loyola: We should always be prepared so as never to err to believe that what I see as white is black, if the hierarchical Church defines it thus.
Pentcho Valev