Non-unitarity or hidden observables?

TL;DR

This paper explores the implications of non-unitarity and hidden observables in conformal field theories across various spacetimes, analyzing spacetime inversion, conformal inversion, and detector state evolution.

Contribution

It provides a detailed analysis of spacetime and conformal inversion effects and clarifies how non-unitary processes coexist with thermal phenomena in quantum field theories.

Findings

Spacetime inversion affects field quantization in Minkowski, de Sitter, and anti-de Sitter spaces.

Non-unitary evolution of detector states can occur without violating thermal effects.

Unitarity is preserved in the presence of non-unitary detector processes through specific mechanisms.

Abstract

A free hermitian conformal field theory is considered in Minkowski, de Sitter and anti-de Sitter spacetimes. The first part of the paper studies spacetime inversion and conformal inversion, wherein their role in the field quantization is elucidated in those spaces. The second part of the paper is concerned with the non-unitary evolution of detector's state. Several examples of such processes are provided with a clarification of how the unitarity is preserved with still having well-known thermal effects.