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arXiv · 2306.07866

Birkhoff Theorem for Berwald Finsler spacetimes

Nicoleta Voicu·Christian Pfeifer·Samira Cheraghchi
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Abstract

Finsler spacetime geometry is a canonical extension of Riemannian spacetime geometry. It is based on a general length measure for curves (which does not necessarily arise from a spacetime metric) and it is used as an effective description of spacetime in quantum gravity phenomenology as well as in extensions of general relativity aiming to provide a geometric explanation of dark energy. A particular interesting subclass of Finsler spacetimes are those of Berwald type, for which the geometry is defined in terms of a canonical affine connection that uniquely generalizes the Levi-Civita connection of a spacetime metric. In this sense, Berwald Finsler spacetimes are Finsler spacetimes closest to pseudo-Riemannian ones. We prove that all Ricci-flat, spatially spherically symmetric Berwald spacetime structures are either pseudo-Riemannian (Lorentzian), or flat. This insight enables us to generalize the Jebsen-Birkhoff theorem to Berwald spacetimes.

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Nicoleta Voicu, Christian Pfeifer, Samira Cheraghchi. 2023-06-13. Birkhoff Theorem for Berwald Finsler spacetimes. https://doi.org/10.1103/physrevd.108.104060

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