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arXiv · 2210.15348

Past-directed scalar field gradients and scalar-tensor thermodynamics

Andrea Giusti·Serena Giardino·Valerio Faraoni
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Abstract

We refine and slightly enlarge the recently proposed first-order thermodynamics of scalar-tensor gravity to include gravitational scalar fields with timelike and past-directed gradients. The implications and subtleties arising in this situation are discussed and an exact cosmological solution of scalar-tensor theory in first-order thermodynamics is revisited in light of these results.

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Andrea Giusti, Serena Giardino, Valerio Faraoni. 2022-10-27. Past-directed scalar field gradients and scalar-tensor thermodynamics. https://doi.org/10.1007/s10714-023-03095-7

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