On the evolution of cosmic-superstring networks

TL;DR

This paper models (p,q) string networks from IIB string theory, showing through numerical evidence that such networks reach a scaling limit rather than freezing, with density increasing with the number of string types.

Contribution

It introduces a field theory model for interacting (p,q) strings and demonstrates that the network avoids freezing, reaching a scaling regime with density growth proportional to the number of string types.

Findings

Networks reach a scaling limit rather than freezing.

Density of the network increases with the number of string types.

Numerical evidence supports the one-scale model explanation.

Abstract

We model the behaviour of a network of interacting (p,q) strings from IIB string theory by considering a field theory containing multiple species of string, allowing us to study the effect of non-intercommuting events due to two different species crossing each other. This then has the potential for a string dominated Universe with the network becoming so tangled that it freezes. We give numerical evidence, explained by a one-scale model, that such freezing does not take place, with the network reaching a scaling limit where its density relative to the background increases with N, the number of string types.