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arXiv · 1911.04830

Thermodynamics of $f(R)$ Theories of Gravity

C. D. Peralta·S. E. Jorás
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Abstract

This paper starts from a toy model for inflation in a class of modified theories of gravity in the metric formalism. Instead of the standard procedure -- assuming a non-linear Lagrangian $f(R)$ in the Jordan frame -- we start from a simple $ϕ^2$ potential in the Einstein frame and investigate the corresponding $f(R)$ in the former picture. The addition of an ad-hoc Cosmological Constant in the Einstein frame leads to a Thermodynamical interpretation of this physical system, which allows further insight on its (meta)stability and evolution.

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C. D. Peralta, S. E. Jorás. 2020-05-25. Thermodynamics of $f(R)$ Theories of Gravity. https://doi.org/10.1088/1475-7516%2F2020%2F06%2F053

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