A covariant entropy conjecture on cosmological dynamical horizon

TL;DR

This paper proposes a covariant entropy conjecture related to the cosmological dynamical horizon and tests its validity across various universe geometries, linking it to thermodynamic principles.

Contribution

It introduces a new covariant entropy conjecture for cosmological horizons and verifies its applicability in different universe models.

Findings

Conjecture holds in open, flat, and closed universes.

Supports a thermodynamic interpretation of cosmological horizons.

Extends the generalized second law to cosmological settings.

Abstract

We here propose a covariant entropy conjecture on cosmological dynamical horizon. After the formulation of our conjecture, we test its validity in adiabatically expanding universes with open, flat and closed spatial geometry, where our conjecture can also be viewed as a cosmological version of the generalized second law of thermodynamics in some sense.