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arXiv · 1504.07287

Elementary derivation of the expressions of momentum and energy in special relativity

Luca Peliti
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Abstract

The expressions of momentum and energy of a particle in special relativity are often derived in a quite unconvincing manner in elementary text, by resorting either to electrodynamic or quantum considerations, or via the introduction of the less-than-elementary concept of a four-vector. It is instead possible, by exploiting considerations introduced by P. Epstein and A. Einstein and exploited later by Feynman, to obtain a fully elementary derivation of these expressions and of the $E=mc^2$ formula exploiting only Lorentz transformations and the postulate of the conservation of quantities defined for point-like particles which reduce to the Newtonian expressions of momentum and energy in the classical limit.

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Luca Peliti. 2015-04-27. Elementary derivation of the expressions of momentum and energy in special relativity. https://arxiv.org/abs/1504.07287

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