A Simple Constructive Proof of Wigner's Theorem

Daniel D. Spiegel

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arXiv · 1810.10111

A Simple Constructive Proof of Wigner's Theorem

Daniel D. Spiegel

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Abstract

This expository note presents a constructive proof of Wigner's theorem using only a few basic facts about Hilbert spaces, such as the existence of orthonormal bases and the Fourier decomposition of a vector. Our proof is based on a proof by Steven Weinberg found in the first volume of his series of textbooks on quantum field theory, but differs in a few places for the sake of greater simplicity and rigor.

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Daniel D. Spiegel. 2022-08-12. A Simple Constructive Proof of Wigner's Theorem. https://arxiv.org/abs/1810.10111

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