The Unruh effect and its applications

TL;DR

This paper reviews the Unruh effect, emphasizing its significance in understanding observer-dependent particle content, black hole radiation, and cosmological horizons, while addressing recent developments and misconceptions.

Contribution

It provides a comprehensive review of the Unruh effect, highlighting its applications, recent advances, and clarifying common misconceptions.

Findings

The Unruh effect demonstrates observer-dependent particle detection.

It is crucial for understanding black hole radiation and cosmological horizons.

Recent developments have expanded its theoretical and experimental understanding.

Abstract

It has been thirty years since the discovery of the Unruh effect. It has played a crucial role in our understanding that the particle content of a field theory is observer dependent. This effect is important in its own right and as a way to understand the phenomenon of particle emission from black holes and cosmological horizons. Here, we review the Unruh effect with particular emphasis to its applications. We also comment on a number of recent developments and discuss some controversies. Effort is also made to clarify what seems to be common misconceptions.