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arXiv · 2406.09251

The Tolman-Ehrenfest criterion of thermal equilibrium in scalar-tensor gravity

Numa Karolinski·Valerio Faraoni
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Abstract

The Tolman-Ehrenfest criterion for the thermal equilibrium of a fluid at rest in a static general-relativistic geometry is generalized to scalar-tensor gravity. Surprisingly, the gravitational scalar field, which fixes the strength of the effective gravitational coupling, does not play a role in determining thermal equilibrium. As a result, heat does not sink more in a gravitational field where gravity is stronger.

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Numa Karolinski, Valerio Faraoni. 2024-06-13. The Tolman-Ehrenfest criterion of thermal equilibrium in scalar-tensor gravity. https://arxiv.org/abs/2406.09251

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