Quark-antiquark potential in defect conformal field theory

TL;DR

This paper studies the quark-antiquark potential in defect conformal field theory by analyzing Wilson lines in N=4 super Yang-Mills at weak and strong coupling, revealing a phase transition in string configurations.

Contribution

It provides a detailed comparison of Wilson line expectation values at weak and strong coupling in the presence of a defect, including the analysis of a phase transition.

Findings

Identification of a Gross-Ooguri phase transition

Explicit string configurations for dual descriptions

Agreement between gauge theory and string results in a double scaling limit

Abstract

We consider antiparallel Wilson lines in N=4 super Yang-Mills in the presence of a codimension-1 defect. We compute the Wilson lines' expectation value both at weak coupling, in the gauge theory, and at strong coupling, by finding the string configurations which are dual to this operator. These configurations display a Gross-Ooguri transition between a connected, U-shaped string phase and a phase in which the string breaks into two disconnected surfaces. We analyze in detail the critical configurations separating the two phases and compare the string result with the gauge theory one in a certain double scaling limit.