Circular Wilson loops in defect Conformal Field Theory

TL;DR

This paper investigates a D3-D5 defect conformal field theory, analyzing circular Wilson loops and demonstrating how weak coupling results can be extrapolated to strong coupling using a double scaling limit involving parameters like the gauge group rank difference and internal space orientation.

Contribution

It introduces a double scaling limit in defect CFTs that connects weak and strong coupling regimes for Wilson loop calculations.

Findings

Weak coupling results can be extrapolated to strong coupling in the double scaling limit.

The vacuum expectation value of circular Wilson loops depends on parameters like $L$, $R$, and $ heta$.

The analysis provides a framework for studying non-perturbative effects in defect CFTs.

Abstract

We study a D3-D5 system dual to a conformal field theory with a codimension-one defect that separates regions where the ranks of the gauge groups differ by $k$. With the help of this additional parameter, as observed by Nagasaki, Tanida and Yamaguchi, one can define a double scaling limit in which the quantum corrections are organized in powers of $\lambda/k^2$, which should allow to extrapolate results between weak and strong coupling regimes. In particular we consider a radius $R$ circular Wilson loop placed at a distance $L$, whose internal space orientation is given by an angle $\chi$. We compute its vacuum expectation value and show that, in the double scaling limit and for small $\chi$ and small $L/R$, weak coupling results can be extrapolated to the strong coupling limit.