English

General relativistic statistical mechanics

General Relativity and Quantum Cosmology 2013-05-01 v2 High Energy Physics - Theory

Abstract

Understanding thermodynamics and statistical mechanics in the full general relativistic context is an open problem. I give tentative definitions of equilibrium state, mean values, mean geometry, entropy and temperature, which reduce to the conventional ones in the non-relativistic limit, but remain valid for a general covariant theory. The formalism extends to quantum theory. The construction builds on the idea of thermal time, on a notion of locality for this time, and on the distinction between global and local temperature. The last is the temperature measured by a local thermometer, and is given by kT = hbar d tau/ds, with k the Boltzmann constant, hbar the Planck constant, ds proper time and d tau the equilibrium thermal time.

Keywords

Cite

@article{arxiv.1209.0065,
  title  = {General relativistic statistical mechanics},
  author = {Carlo Rovelli},
  journal= {arXiv preprint arXiv:1209.0065},
  year   = {2013}
}

Comments

A tentative second step in the thermal time direction, 10 years after the paper with Connes. The aim is the full thermodynamics of gravity. The language of the paper is a bit technical: look at the Appendix first (expanded in version 2)

R2 v1 2026-06-21T21:58:20.835Z