Thermodynamics of scalar-tensor gravity
نویسندگان
چکیده
Previously, the Einstein equation has been described as an of state, general relativity equilibrium state gravity, and $f({\cal R})$ gravity a non-equilibrium one. We apply Eckart's first order thermodynamics to effective dissipative fluid describing scalar-tensor gravity. Surprisingly, we obtain simple expressions for heat flux, "temperature gravity", shear bulk viscosity, entropy density, plus generalized Fourier law in consistent Eckart thermodynamical picture. Well-defined notions temperature approach equilibrium, missing current spacetime scenarios, naturally emerge.
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ژورنال
عنوان ژورنال: Physical review
سال: 2021
ISSN: ['0556-2813', '1538-4497', '1089-490X']
DOI: https://doi.org/10.1103/physrevd.103.l121501