Can we trust semiclassical description of particle creation?

TL;DR

This paper investigates the reliability of semiclassical particle creation predictions when the source of the classical background is quantized, finding that in certain cases, particle creation is entirely suppressed.

Contribution

It demonstrates that quantizing the background source can negate semiclassical particle creation in specific cosmological and particle physics scenarios.

Findings

Semiclassical particle creation can be completely blocked when the background source is quantized.

Quantization of the background source significantly alters predictions of particle creation.

Results challenge the validity of semiclassical approaches in certain stable universe models.

Abstract

The predictions of the semiclassical description of particle creation based on QFT in classical backgrounds may be significantly modified when the source of the classical background is also quantized and backreaction is taken into account. In the cases of a stable charged particle, expanding empty (Milne) universe, and de Sitter universe with a true cosmological constant, the semiclassical particle creation is completely blocked up.