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Although Einstein's name is closely linked with the celebrated relation E =mc2 between mass and energy, a critical examination of the more than half dozen"proofs" of this relation that Einstein produced over a span of forty yearsreveals that all these proofs suffer from mistakes. Einstein introducedunjustified assumptions, committed fatal errors in logic, or adopted low-speed,restrictive approximations. He never succeeded in producing a valid generalproof applicable to a realistic system with arbitrarily large internal andexternal (that is, translational) speeds. The first such general proof wasproduced by Max Laue in 1911 (for "closed" systems with a time-independentenergy-momentum tensor) and it was generalized by Felix Klein in 1918 (forarbitrary time-dependent "closed" systems).

Einstein's E = mc^2 mistakes