Comment on 'New perspective on thermodynamics of spacetime: The emergence of unimodular gravity and the equivalence of entropies'

TL;DR

This paper discusses a formal similarity between two approaches to spacetime thermodynamics, highlighting potential implications for understanding the physical significance of curvature and energy-momentum ambiguities.

Contribution

It provides a critical commentary linking different formulations of spacetime curvature and thermodynamics, emphasizing their formal resemblance and discussing its physical implications.

Findings

Identifies a formal resemblance between curvature scale expressions

Highlights the physical significance of the energy-momentum ambiguity

Suggests potential insights into spacetime thermodynamics

Abstract

In this comment on the article by Alonso-Serrano and Liska (arXiv: 2008.04805) a formal resemblance between their expression of curvature scale and the scale dependent on the matter energy-momentum ambiguity of Finkelstein et al (JMP, 2001) is pointed out. Physical significance of this observation is also discussed.