John Stachel: "But this seems to be nonsense. How can it happen that the speed of light relative to an observer cannot be increased or decreased if that observer moves towards or away from a light beam? Einstein states that he wrestled with this problem over a lengthy period of time, to the point of despair." http://www.aip.org/history/exhibits/...relativity.htm

Updated 2014 by Don Koks. Original by Steve Carlip (1997) and Philip Gibbs 1996: "To state that the speed of light is independent of the velocity of the observer is very counterintuitive. Some people even refuse to accept this as a logically consistent possibility, but in 1905 Einstein was able to show that it is perfectly consistent if you are prepared to give up assumptions about the absolute nature of space and time." http://math.ucr.edu/home/baez/physic..._of_light.html

So Einstein "wrestled with this problem over a lengthy period of time, to the point of despair", but in the end found it profitable to introduce the nonsense. However the nonsense naturally proved inconsistent with the non-nonsensical concepts of space and time, and Einstein restored consistency by converting space and time, too, into nonsense (insanity is often internally consistent):

"Special relativity is based on the observation that the speed of light is always the same, independently of who measures it, or how fast the source of the light is moving with respect to the observer. Einstein demonstrated that as an immediate consequence, space and time can no longer be independent, but should rather be considered a new joint entity called "spacetime." http://community.bowdoin.edu/news/20...rs-of-gravity/

http://negrjp.fotoblog.uol.com.br/im...0819051851.jpg

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