Dualities of the entropy bound

TL;DR

This paper investigates a hypothetical thermodynamic system at the Hubble entropy bound, demonstrating its invariance under string theory dualities and M-theory dimension exchanges, and explores the uniqueness of this entropy bound.

Contribution

It reveals the invariance of the Hubble entropy bound system under string dualities and M-theory dimension exchanges, highlighting its potential fundamental significance.

Findings

System saturating Hubble entropy bound is duality invariant.

The entropy bound's uniqueness under dualities is discussed.

Implications for fundamental theories are considered.

Abstract

I study the hypothetical thermodynamic system which saturates the so-called Hubble entropy bound and show that it is invariant under the S- and T-dualities of string theory as well as the interchanges of the eleventh dimension of M-theory. I also discuss how unique the entropy bound is under the dualities and some related issues.