Stochastic collapse

TL;DR

This paper explores how quantum fluctuations influence the dynamics of scalar fields in cosmological collapse models, revealing potential instabilities below the Planck scale through a stochastic formalism.

Contribution

It introduces a stochastic approach to analyze quantum fluctuations in scalar field cosmologies, highlighting their impact on collapse stability and equation of state perturbations.

Findings

Quantum fluctuations induce stochastic noise in scalar field dynamics.

Large-scale perturbations can lead to quantum instabilities in collapse models.

Stochastic formalism modifies classical collapse behavior at sub-Planckian scales.

Abstract

We investigate cosmological models described by a scalar field with an exponential potential, and apply the stochastic formalism, which allows us to study how quantum field fluctuations give rise to stochastic noise. This modifies the classical dynamics of the scalar field at large scales, above a coarse-graining scale. In particular we explore how quantum field fluctuations perturb the equation of state on large scales which can lead to a quantum instability of the classical collapse solution below the Planck scale in the case of a pressureless collapse.