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arXiv · 2006.06001

Quasilocal conservation laws in cosmology: a first look

Marius Oltean·Hossein Bazrafshan Moghaddam·Richard J. Epp
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Abstract

Quasilocal definitions of stress-energy-momentum---that is, in the form of boundary densities (in lieu of local volume densities)---have proven generally very useful in formulating and applying conservation laws in general relativity. In this essay, we take a first basic look into applying these to cosmology, specifically using the Brown-York quasilocal stress-energy-momentum tensor for matter and gravity combined. We compute this tensor and present some simple results for a flat FLRW spacetime with a perfect fluid matter source.

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Marius Oltean, Hossein Bazrafshan Moghaddam, Richard J. Epp. 2020-06-10. Quasilocal conservation laws in cosmology: a first look. https://doi.org/10.1142/s0218271820430294

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