Thermal behavior induced by vacuum polarization on causal horizons in comparison with the standard heat bath formalism

TL;DR

This paper explores the thermal effects of vacuum polarization on causal horizons using algebraic quantum field theory, revealing an area-dependent entropy behavior distinct from standard heat bath thermality.

Contribution

It introduces an algebraic approach to unify the thermal phenomena caused by vacuum fluctuations and standard heat baths, highlighting the role of localization and holography.

Findings

Vacuum polarization on wedge horizons is compressed into the lightray direction.

Entropy-like measures exhibit area dependence due to localization effects.

Localization-induced temperature is determined by geometric properties.

Abstract

Modular theory of operator algebras and the associated KMS property are used to obtain a unified description for the thermal aspects of the standard heat bath situation and those caused by quantum vacuum fluctuations from localization. An algebraic variant of lightfront holography reveals that the vacuum polarization on wedge horizons is compressed into the lightray direction. Their absence in the transverse direction is the prerequisite to an area (generalized Bekenstein-) behavior of entropy-like measures which reveal the loss of purity of the vacuum due to restrictions to wedges and their horizons. Besides the well-known fact that localization-induced (generalized Hawking-) temperature is fixed by the geometric aspects, this area behavior (versus the standard volume dependence) constitutes the main difference between localization-caused and standard thermal behavior.