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arXiv · 1908.10022

Lorentzian angles and trigonometry including lightlike vectors

Rafael D. Sorkin
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Abstract

We define a concept of Lorentzian angle that works even when one or both of the directions involved is null (lightlike). Such angles play a role in Regge-Calculus, in the boundary- and corner- terms for the gravitational action, and in the Lorentzian Gauss-Bonnet theorem (for which we provide a proof).

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Rafael D. Sorkin. 2020-02-06. Lorentzian angles and trigonometry including lightlike vectors. https://arxiv.org/abs/1908.10022

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