Brian Greene: What does it mean for the speed of light to be constant? https://www.youtube.com/watch?v=-Irlq3TFr8Q

Is the speed of light, as measured by the receiver, independent of the motion of the receiver? Of course not:

Stationary light source; moving receiver: http://www.einstein-online.info/imag...ector_blue.gif

(Website: http://www.einstein-online.info/spotlights/doppler.html)

The speed of the light pulses relative to 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 relative to the receiver is

c'= df' c

where f' f is the frequency measured by the receiver.

Einstein's constant-speed-of-light postulate is obviously false. Many physicists know that and even try to tell the truth sometimes but there is a problem. Fundamental physics is entirely based on the false constancy and will collapse without it. In this sense telling the truth is suicidal:

Joao Magueijo, Faster Than the Speed of Light, p. 250: "Lee [Smolin] and I discussed these paradoxes at great length for many months, starting in January 2001. We would meet in cafés in South Kensington or Holland Park to mull over the problem. THE ROOT OF ALL THE EVIL was clearly SPECIAL RELATIVITY. All these paradoxes resulted from well known effects such as length contraction, time dilation, or E=mc^2, all basic predictions of special relativity. And all denied the possibility of establishing a well-defined border, common to all observers, capable of containing new quantum gravitational effects." http://www.amazon.com/Faster-Than-Sp.../dp/0738205257

"...Dr. Magueijo said. "We need to drop a postulate, perhaps the constancy of the speed of light." http://www.nytimes.com/2002/12/31/sc...-relative.html

"The speaker Joao Magueijo, is a Reader in Theoretical Physics at Imperial College, London and author of Faster Than the Speed of Light: The Story of a Scientific Speculation. He opened by explaining how Einstein's theory of relativity is the foundation of every other theory in modern physics and that the assumption that the speed of light is constant is the foundation of that theory. Thus a constant speed of light is embedded in all of modern physics and to propose a varying speed of light (VSL) is worse than swearing! It is like proposing a language without vowels." http://www.thegreatdebate.org.uk/VSLRevPrnt.html

"The whole of physics is predicated on the constancy of the speed of light," Joao Magueijo, a cosmologist at Imperial College London and pioneer of the theory of variable light speed, told Motherboard. "So we had to find ways to change the speed of light without wrecking the whole thing too much." https://motherboard.vice.com/en_us/a...t-speed-slowed

Pentcho Valev