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arXiv · 2010.09433

Spherical-harmonic tensors

Francisco Gonzalez Ledesma·Matthew Mewes
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Abstract

The connection between spherical harmonics and symmetric tensors is explored. For each spherical harmonic, a corresponding traceless symmetric tensor is constructed. These tensors are then extended to include nonzero traces, providing an orthonormal angular-momentum eigenbasis for symmetric tensors of any rank. The relationship between the spherical-harmonic tensors and spin-weighted spherical harmonics is derived. The results facilitate the spherical-harmonic expansion of a large class of tensor-valued functions. Several simple illustrative examples are discussed, and the formalism is used to derive the leading-order effects of violations of Lorentz invariance in Newtonian gravity.

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Francisco Gonzalez Ledesma, Matthew Mewes. 2020-10-13. Spherical-harmonic tensors. https://doi.org/10.1103/physrevresearch.2.043061

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