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A rigorous minimum-assumption derivation of the Lorentz transformation

The available derivations of the Lorentz transformation (LT) are of questionable validity because they introduce some assumptions in addition to Einstein's two fundamental postulates or, even if they do not do so, are highly abstract and abstruse (as is the case with two or three 'exact' derivations). The rigorous LT derivation proposed in this paper has only the constant speed of light and two thought experiments as its underlying assumptions. With the constant speed of light used to prove all the necessary assumptions, no additional assumptions are needed. Our systematic approach explains in a convincing way why stress is irrelevant to length contraction.