A stable static Universe?

TL;DR

This paper investigates the stability of a static closed universe filled with radiation, considering emergent gravity and environmental effects, and finds conditions under which the universe remains stable.

Contribution

It introduces a framework where general relativity is emergent and analyzes the stability of a static universe in this context, incorporating environmental interactions.

Findings

Static universe can be stable under certain conditions.

Effective free energy analysis supports stability.

Emergent gravity influences cosmological stability.

Abstract

Starting from the assumption that general relativity might be an emergent phenomenon showing up at low-energies from an underlying microscopic structure, we re-analyze the stability of a static closed Universe filled with radiation. In this scenario, it is sensible to consider the effective general-relativistic configuration as in a thermal contact with an "environment" (the role of environment can be played, for example, by the higher-dimensional bulk or by the trans-Planckian degrees of freedom). We calculate the free energy at a fixed temperature of this radiation-filled static configuration. Then, by looking at the free energy we show that the static Einstein configuration is stable under the stated condition.