Tunneling dynamics in cosmological bounce models

TL;DR

This paper uses quasiclassical methods to analyze tunneling times in quantum cosmological bounce models, revealing potential issues with singularity avoidance and quantum stability.

Contribution

It introduces a novel approach to defining tunneling times in bounce models, providing new insights beyond traditional tunneling probability methods.

Findings

Tunneling times remain small even for large barriers.

Quantum dynamics may reach zero scale factor, questioning singularity avoidance.

Bounce models exhibit quantum instability.

Abstract

Quasiclassical methods are used to define dynamical tunneling times in models of quantum cosmological bounces. These methods provide relevant new information compared with the traditional treatment of quantum tunneling by means of tunneling probabilities. As shown here, the quantum dynamics in bounce models is not secure from reaching zero scale factor, re-opening the question of how the classical singularity may be avoided. Moreover, in the examples studied here, tunneling times remain small even for large barriers, highlighting the quantum instability of underlying bounce models.