On the nature of cosmic strings in the brane world

TL;DR

This paper analyzes the properties of cosmic strings in brane world scenarios, revealing conditions for tension enhancement and potential solutions to the cosmic string problem relevant for post-inflationary string formation.

Contribution

It provides a non-perturbative analysis of cosmic strings on the brane, identifying conditions for tension enhancement and proposing a new way to address the cosmic string problem.

Findings

Large enhancement of effective string tension when energy density exceeds twice the brane tension.

A novel method to evade the cosmic string problem near the critical energy density.

Implications for detecting cosmic strings generated after inflation on the brane.

Abstract

We investigate a static, cylindrically symmetric cosmic string on the brane without a perturbative approximation. We find there could be a (large) enhancement of the (effective) string tension when the energy density at the center of the string is (much) larger than twice the brane tension. We also point out a new way to evade the cosmic string problem when the energy density at the center of the string approaches twice the brane tension. These findings could have experimental and theoretical implications for searching for cosmic strings on the brane, in particular for cosmic strings generated after inflation (such as D-term inflation) on the brane.