# Nature of the Vacuum inside the Color Flux Tube

## TL;DR

This paper investigates the internal structure of the color flux tube in quantum chromodynamics, testing the dual superconductivity model and analytical predictions at critical points, with numerical validation in a 3D Z2 gauge model.

## Contribution

It provides the first numerical verification of the dual superconductivity conjecture and analytical predictions for the flux tube structure at the deconfinement transition.

## Key findings

- Complete agreement between numerical results and theoretical predictions.
- Validation of the dual superconductivity model inside the flux tube.
- Analytic expression for Polyakov correlator at the critical point.

## Abstract

The interior of the color flux tube joining a quark pair can be probed by evaluating the correlator of pair of Polyakov loops in a vacuum modified by another Polyakov pair, in order to check the dual superconductivity conjecture which predicts a deconfined, hot core. We also point out that at the critical point of any 3D gauge theories with a continuous deconfining transition the Svetitsky-Yaffe conjecture provides us with an analytic expression of the Polyakov correlator as a function of the position of the probe inside the flux tube. Both these predictions are compared with numerical results in 3D Z2 gauge model finding complete agreement.