Erasure of Strings and Vortexes

TL;DR

This paper investigates the erasure of strings and vortexes during interactions with defects, revealing a universal mechanism where strings are absorbed and dissolved, with implications for cosmology and fundamental physics.

Contribution

It introduces a general phenomenon of string erasure during defect interactions and confirms it through numerical simulation of vortex-wall interactions.

Findings

Strings are almost certainly erased when encountering defects.

Numerical simulation confirms vortex absorption by a domain wall.

The erasure mechanism has broad implications for cosmology and fundamental theories.

Abstract

The interaction of defects can lead to a phenomenon of erasure. During this process, a lower-dimensional object gets absorbed and dissolved by a higher-dimensional one. The phenomenon is very general and has a wide range of implications, both cosmological and fundamental. In particular, all types of strings, such as cosmic strings, QCD flux tubes, or fundamental strings, get erased when encountering a defect, either solitonic or a $D$-brane that deconfines their fluxes. This leads to a novel mechanism of cosmic string break-up, accompanied by gravitational and electromagnetic radiations. The arguments based on loss of coherence and the entropy count suggest that the erasure probability is very close to one, and strings never make it through the deconfining layer. We confirm this by a numerical simulation of the system, which effectively captures the essence of the phenomenon: a $2+1$-dimensional problem of interaction between a Nielsen-Olesen vortex of a $U(1)$ Higgs model and a domain wall inside which the $U(1)$ gauge group is unHiggsed and the magnetic flux is deconfined. In accordance with the entropy argument, in our simulation, the vortex never makes it across the wall.