Anisotropic D3-D5 black holes with unquenched flavors

TL;DR

This paper constructs an analytic anisotropic black hole solution in supergravity with unquenched flavors, modeling a layered defect system in a gauge theory, and analyzes its thermodynamics and transport properties.

Contribution

It provides the first analytic supergravity solution for a layered defect system with backreacted unquenched flavors in the Veneziano limit.

Findings

The solution describes a 2+1 dimensional defect in a 3+1 dimensional gauge theory.

Transport coefficients are computed for perturbations along the defect.

Excitations within a layer behave as an effective D2-brane system.

Abstract

We construct a black hole geometry generated by the intersection of $N_c$ color D3- branes and $N_f$ flavor D5-branes along a 2+1 dimensional subspace. Working in the Veneziano limit in which $N_f$ is large and distributing homogeneously the D5-branes in the internal space, we calculate the solution of the equations of motion of supergravity plus sources which includes the backreaction of the flavor branes. The solution is analytic and dual to a 2+1 dimensional defect in a 3+1 dimensional gauge theory, with $N_f$ massless hypermultiplets living in the defect. The smeared background we obtain can be regarded as the holographic realization of a multilayered system. We study the thermodynamics of the resulting spatially anisotropic geometry and compute the first and second order transport coefficients for perturbations propagating along the defect. We find that, in our system, the dynamics of excitations within a layer can be described by a stack of effective D2-branes.