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arXiv · 2208.04051

Scalar field as a perfect fluid: thermodynamics of minimally coupled scalars and Einstein frame scalar-tensor gravity

Valerio Faraoni·Serena Giardino·Andrea Giusti·Robert Vanderwee
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Abstract

We revisit the analogy between a minimally coupled scalar field in general relativity and a perfect fluid, correcting previous identifications of effective temperature and chemical potential. This provides a useful complementary picture for the first-order thermodynamics of scalar-tensor gravity, paving the way for the Einstein frame formulation (which eluded previous attempts) and raises interesting questions to further develop the analogy.

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Valerio Faraoni, Serena Giardino, Andrea Giusti, Robert Vanderwee. 2022-08-08. Scalar field as a perfect fluid: thermodynamics of minimally coupled scalars and Einstein frame scalar-tensor gravity. https://doi.org/10.1140/epjc/s10052-023-11186-7

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