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Gauss Sums and Quantum Mechanics

Vernon Armitage·Alice Rogers
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Abstract

By adapting Feynman's sum over paths method to a quantum mechanical system whose phase space is a torus, a new proof of the Landsberg-Schaar identity for quadratic Gauss sums is given. In contrast to existing non-elementary proofs, which use infinite sums and a limiting process or contour integration, only finite sums are involved. The toroidal nature of the classical phase space leads to discrete position and momentum, and hence discrete time. The corresponding `path integrals' are finite sums whose normalisations are derived and which are shown to intertwine cyclicity and discreteness to give a finite version of Kelvin's method of images.

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Vernon Armitage, Alice Rogers. 2000-03-22. Gauss Sums and Quantum Mechanics. https://doi.org/10.1088/0305-4470%2F33%2F34%2F305

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