Understanding confinement in Yang–Mills theories

Establish a comprehensive theoretical explanation of confinement in non-Abelian Yang–Mills gauge theories, identifying the mechanisms that produce color confinement and the emergence of confining flux tubes across relevant regimes.

Background

The paper investigates the reconfined phase of trace-deformed SU(2) Yang–Mills theory in (2+1) dimensions, focusing on the behavior of the confining flux tube through an Effective String Theory (EST) description. While several properties appear conserved under trace deformation, it remains fundamentally important to understand the origin and mechanism of confinement in Yang–Mills theories.

By studying Polyakov-loop correlators and comparing with EST predictions, the authors provide evidence that the reconfined phase aligns with the rigid-string (Polchinski–Yang) regime rather than the standard Nambu–Goto description. Despite these advances in a specific setting, the overarching problem of fully understanding confinement in Yang–Mills theories remains open.