Diffusion of massive particles around an Abelian-Higgs string

TL;DR

This paper investigates how massive particles diffuse around an Abelian-Higgs string in the early universe, revealing that string parameters influence particle distribution and potential cosmological density fluctuations.

Contribution

It models particle diffusion as a two-dimensional random walk governed by geodesic equations in the string's spacetime, linking string parameters to particle overdensities.

Findings

Overdensity of particles observed near the string for specific energies and angular momenta.

String parameters influence the distribution and density fluctuations of particles.

Potential cosmological implications due to density fluctuations around the string.

Abstract

We study the diffusion of massive particles in the space time of an Abelian Higgs string. The particles in the early universe plasma execute Brownian motion. This motion of the particles is modeled as a two dimensional random walk in the plane of the Abelian Higgs string. The particles move randomly in the space time of the string according to their geodesic equations. We observe that for certain values of their energy and angular momentum, an overdensity of particles is observed close to the string. We find that the string parameters determine the distribution of the particles. We make an estimate of the density fluctuation generated around the string as a function of the deficit angle. Though the thickness of the string is small, the length is large and the overdensity close to the string may have cosmological consequences in the early universe.