Canonical and path integral quantisation of string cosmology models

TL;DR

This paper explores the quantisation of string cosmology models with scale factor duality, using phase space reduction and path integral methods to compute transition amplitudes and clarify instanton-like behaviors.

Contribution

It demonstrates the consistency of phase space reduction and path integral approaches in quantising duality-invariant string cosmology models.

Findings

Transition amplitudes for classically allowed and forbidden processes computed.

Path integral approach clarifies instanton-like transition behaviors.

Methods are shown to be consistent in this context.

Abstract

We discuss the quantisation of a class of string cosmology models that are characterized by scale factor duality invariance. We compute the amplitudes for the full set of classically allowed and forbidden transitions by applying the reduce phase space and the path integral methods. We show that these approaches are consistent. The path integral calculation clarifies the meaning of the instanton-like behaviour of the transition amplitudes that has been first pointed out in previous investigations.