Field theory simulation of Abelian-Higgs cosmic string cusps

TL;DR

This paper presents a lattice field theory simulation of cusps in Abelian-Higgs cosmic strings, confirming that overlapping string regions near cusps emit radiation and detailing the conditions for string evaporation.

Contribution

It provides the first detailed simulation showing how cusp overlaps lead to radiation emission and string evaporation in Abelian-Higgs cosmic strings.

Findings

Overlap regions near cusps emit radiation.

String cores must touch with radius ~1 for evaporation.

Later cusps are smaller and resemble kinks.

Abstract

We have performed a lattice field theory simulation of cusps in Abelian-Higgs cosmic strings. The results are in accord with the theory that the portion of the strings which overlaps near the cusp is released as radiation. The radius of the string cores which must touch to produce the evaporation is approximately $r = 1$ in natural units. In general, the modifications to the string shape due to the cusp may produce many cusps later in the evolution of a string loop, but these later cusps will be much smaller in magnitude and more closely resemble kinks.