Global cosmic string networks as a function of tension

TL;DR

This study examines how global cosmic string network properties depend on tension, coupling, and damping, revealing the sensitivity of string density to these parameters and highlighting gaps in existing models.

Contribution

It provides new insights into the dependence of cosmic string network density on tension and damping, suggesting improvements for semi-analytical models.

Findings

String density varies with tension-to-coupling ratio.

Existing models lack some key aspects of network dynamics.

Results guide future model enhancements.

Abstract

We investigate the properties of global cosmic string networks as a function of the ratio of string tension to Goldstone-field coupling, and as a function of the Hubble damping strength. Our results show unambiguously that the string density is sensitive to this ratio. We also find that existing semi-analytical (one-scale) models must be missing some important aspect of the network dynamics. Our results point the way towards improving such models.