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arXiv · 2206.02046

Peculiar thermal states in the first-order thermodynamics of gravity

Valerio Faraoni·Andrea Giusti·Sonia Jose·Serena Giardino
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Abstract

In the context of the recently proposed first-order thermodynamics of scalar-tensor gravity, we discuss the possibility of zero-temperature states of equilibrium other than Einstein gravity, including pathological Brans-Dicke theory, Palatini $f(R)$ gravity, and cuscuton gravity, all with non-dynamical scalar fields. The formalism is extended to Nordstr\"om gravity, which contains only a scalar degree of freedom and has negative temperature relative to general relativity.

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Valerio Faraoni, Andrea Giusti, Sonia Jose, Serena Giardino. 2022-06-04. Peculiar thermal states in the first-order thermodynamics of gravity. https://doi.org/10.1103/physrevd.106.024049

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