Cosmic String Structure at the Gravitational Radiation Scale

TL;DR

This paper investigates the small-scale structure of cosmic strings and refines the understanding of their gravitational radiation length scale, suggesting the existence of two distinct loop populations near different size scales.

Contribution

It develops a model of small-scale structure on cosmic strings and proposes that the gravitational radiation cutoff is smaller than previously thought, supported by recent simulations.

Findings

Gravitational radiation length scale is smaller than $ au ightarrow au_{GR}$

Existence of two cosmic string loop populations near horizon and cutoff scales

Recent simulations support the dual-population model

Abstract

We use our model of the small scale structure on cosmic strings to develop further the result of Siemens, Olum, and Vilenkin that the gravitational radiation length scale on cosmic strings is smaller than the previously assumed $\Gamma G\mu t$. We discuss some of the properties of cosmic string loops at this cutoff scale, and we argue that recent network simulations point to two populations of cosmic string loops, one near the horizon scale and one near the gravitational radiation cutoff.