English

First-order thermodynamics of scalar-tensor cosmology

General Relativity and Quantum Cosmology 2022-05-06 v1

Abstract

A new thermodynamics of scalar-tensor gravity is applied to spatially homogeneous and isotropic cosmologies in this class of theories and tested on analytical solutions. A forever-expanding universe approaches the Einstein "state of equilibrium" with zero effective temperature at late times and departs from it near spacetime singularities. "Cooling" by expansion and "heating" by singularities compete near the Big Rip, where it is found that the effective temperature diverges in the case of a conformally coupled scalar field.

Keywords

Cite

@article{arxiv.2202.07393,
  title  = {First-order thermodynamics of scalar-tensor cosmology},
  author = {Serena Giardino and Valerio Faraoni and Andrea Giusti},
  journal= {arXiv preprint arXiv:2202.07393},
  year   = {2022}
}

Comments

18 pages, no figures