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arXiv · 2010.07329

A New Action for Cosmology

David Sloan
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Abstract

We present a new action which reproduces the cosmological sector of general relativity in both the Friedmann-Lemaitre-Robertson-Walker (FLRW) and Bianchi models. This action makes no reference to the scale factor, and is of a frictional type first examined by Herglotz. We demonstrate that the extremization of this action reproduces the usual dynamics of physical observables, and the symplectification of this action is the Einstein-Hilbert action for cosmological models. We end by discussing some of the increased explanatory power produced by considering the reduced physical ontology resulting from eliminating scale.

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David Sloan. 2020-10-14. A New Action for Cosmology. https://doi.org/10.1103/physrevd.103.043524

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