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I'm concerned about your book. I got up to this part:JollyOlly said:Baggins101 - you would probably find my book 'A Roller Coaster Ride through Relativity' on Wikibooks of interest.
While most scientists tried to explain this result away by means of various subterfuges, Albert Einstein merely accepted it as a necessary consequence of the Fundamental Principle namely:
The speed of light in a vacuum is a universal constant and will always be the same even when measured by different observers in relative motion.
And I got very concerned. Although what you say is true, the fact that you put the last part of the quote in a box, like you did for what you called the Fundamental Principle and its restated version, gave me the impression that you believe that part of the quote is his second postulate. But you are specifically stating that there really is only one principle or postulate and this misrepresents not only what Einstein said but also the fundamental basis for Special Relativity.
The actual statement of his second postulate from the introduction of his 1905 paper is:
light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body.
Or later at the beginning of section 2:
Any ray of light moves in the “stationary” system of co-ordinates with the determined velocity c, whether the ray be emitted by a stationary or by a moving body.
When he says the "definite velocity c" or the "determined velocity c", he is referring to his comment at the end of the first section where he defines c to be the measured two-way speed of light.
But his second postulate is about the unmeasurable one-way speed of light which cannot be part of the first postulate. That's what he means by "propagated" or "ray". He's defining the one-way speed of light to be identical to the two-way speed of light in any system of co-ordinates.
This is my concern about your book. Do you eventually clarify this issue?