On the holographic width of flux tubes

TL;DR

This paper uses gauge/gravity duality to analyze the flux tube width between static quarks, confirming the universal logarithmic broadening in confining backgrounds and studying transverse string fluctuations in curved spaces.

Contribution

It introduces a formalism to compute flux tube width via minimal surfaces in holographic backgrounds, demonstrating universality and analyzing transverse fluctuations in curved geometries.

Findings

Logarithmic broadening of flux tubes is universal in confining backgrounds.

The formalism applies to AdS space for transverse fluctuation analysis.

Transverse deviations of the string are quantitatively computed in curved backgrounds.

Abstract

We investigate the width of the flux tube between heavy static quark charges. Using the gauge/gravity duality, we find the properties of the minimal connected surface related to the width of the bound state. We show that in the confining phase, the logarithmic broadening predicted by the effective string description and observed in lattice simulations is a generic property of all confining backgrounds. We also study the transverse fluctuations of the string connecting two static quarks in curved backgrounds. Our formalism is applied to AdS space where we compute the expectation value of the square of transverse deviations of the string, a quantity related to the width.