Troubles with quantum anisotropic cosmological models: loss of unitarity

TL;DR

This paper investigates the quantization of anisotropic Bianchi I cosmological models with perfect fluid, revealing non-unitarity issues that challenge the equivalence of different quantum interpretations.

Contribution

It demonstrates that quantizing Bianchi I models with Schutz formalism leads to non-unitary evolution, highlighting fundamental issues in quantum cosmology.

Findings

Model exhibits non-unitarity during quantization

Breaks equivalence between many-worlds and dBB interpretations

Highlights challenges in quantum cosmological models

Abstract

The anisotropic Bianchi I cosmological model coupled with perfect fluid is quantized in the minisuperspace. The perfect fluid is described by using the Schutz formalism which allows to attribute dynamical degrees of freedom to matter. It is shown that the resulting model is non-unitary. This breaks the equivalence between the many-worlds and dBB interpretations of quantum mechanics.