All right guys. I'm in another chapter of Cox - Why E=mc^2 and I desired to compute basic equations from Einstein based on the texts of this ebook. Now I understood the concepts this way as you can see on the picture ^^^. In fact this has to do with definition of gamma, which is coefficient used widely for relativity computations. I defined one such computation based on times t1 and t2 of observer, inhabitant.

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