Gravity duals for the Coulomb branch of marginally deformed N=4 Yang-Mills

TL;DR

This paper constructs supergravity duals for the Coulomb branch of marginally deformed N=4 SYM, analyzing Wilson loops, screening, confinement, and spectra of excitations, revealing new integrable structures and potential behaviors.

Contribution

It introduces a method to derive supergravity backgrounds for marginal deformations of N=4 SYM on the Coulomb branch, including detailed spectral analysis beyond the s-wave approximation.

Findings

Wilson loop expectation values confirm Coulombic behavior in the conformal case

Complete screening and confining regimes are identified depending on parameters

Explicit solutions relate to Heun equations and Inozemtsev integrable system

Abstract

Supergravity backgrounds dual to a class of exactly marginal deformations of N supersymmetric Yang-Mills can be constructed through an SL(2,R) sequence of T-dualities and coordinate shifts. We apply this transformation to multicenter solutions and derive supergravity backgrounds describing the Coulomb branch of N=1 theories at strong 't Hooft coupling as marginal deformations of N=4 Yang-Mills. For concreteness we concentrate to cases with an SO(4)xSO(2) symmetry preserved by continuous distributions of D3-branes on a disc and on a three-dimensional spherical shell. We compute the expectation value of the Wilson loop operator and confirm the Coulombic behaviour of the heavy quark-antiquark potential in the conformal case. When the vev is turned on we find situations where a complete screening of the potential arises, as well as a confining regime where a linear or a logarithmic potential prevails depending on the ratio of the quark-antiquark separation to the typical vev scale. The spectra of massless excitations on these backgrounds are analyzed by turning the associated differential equations into Schrodinger problems. We find explicit solutions taking into account the entire tower of states related to the reduction of type-IIB supergravity to five dimensions, and hence we go beyond the s-wave approximation that has been considered before for the undeformed case. Arbitrary values of the deformation parameter give rise to the Heun differential equation and the related Inozemtsev integrable system, via a non-standard trigonometric limit as we explicitly demonstrate.