Particle Production in Matrix Cosmology

TL;DR

This paper investigates particle production in 1+1 dimensional string theory's matrix cosmology, showing how the matrix model resolves vacuum ambiguity and results in finite energy density, counteracting anomalous particle production.

Contribution

It introduces a matrix model approach to resolve vacuum ambiguity and demonstrates finite energy density in cosmological particle production.

Findings

Finite energy density cancels anomalous particle production

Matrix model resolves vacuum ambiguity

Explicit mode expansions discussed

Abstract

We consider cosmological particle production in 1+1 dimensional string theory. The process is described most efficiently in terms of anomalies, but we also discuss the explicit mode expansions. In matrix cosmology the usual vacuum ambiguity of quantum fields in time-dependent backgrounds is resolved by the underlying matrix model. This leads to a finite energy density for the "in" state which cancels the effect of anomalous particle production.