Thermodynamic Origin of the Null Energy Condition

TL;DR

This paper derives the null energy condition from thermodynamic principles, suggesting it is a fundamental property of gravity rather than just matter, by linking it to the second law of thermodynamics and black hole entropy.

Contribution

It provides a novel derivation of the null energy condition from thermodynamics, highlighting its fundamental role in gravitational physics.

Findings

Null energy condition derived from thermodynamics

Links gravity properties to thermodynamic laws

Supports gravity as the origin of energy constraints

Abstract

We derive the classical null energy condition, understood as a constraint on the Ricci tensor, from the second law of thermodynamics applied locally to Bekenstein-Hawking entropy associated with patches of null congruences. The derivation provides evidence that the null energy condition, which has usually been regarded as a condition on matter, is fundamentally a property of gravity.