Near-horizon solutions for D3-branes ending on 5-branes

TL;DR

This paper constructs supergravity solutions describing D3-branes ending on 5-branes, providing holographic duals to 4d N=4 SYM with boundary conditions, and compares strong coupling results with weak coupling expectations.

Contribution

It presents explicit near-horizon supergravity solutions for D3-branes ending on 5-branes, matching boundary conditions classified by Gaiotto and Witten, and explores their holographic implications.

Findings

Solutions match the Gaiotto-Witten classification

One-point functions computed at strong coupling differ from weak coupling expectations

Solutions can be interpreted as duals of N=4 SYM on AdS_4 with boundary conditions

Abstract

We construct the type IIB supergravity solutions describing D3-branes ending on 5-branes, in the near-horizon limit of the D3-branes. Our solutions are holographically dual to the 4d N=4 SU(N) super-Yang-Mills (SYM) theory on a half-line, at large N and large 't Hooft coupling, with various boundary conditions that preserve half of the supersymmetry. The solutions are limiting cases of the general solutions with the same symmetries constructed in 2007 by D'Hoker, Estes and Gutperle. The classification of our solutions matches exactly with the general classification of boundary conditions for D3-branes ending on 5-branes by Gaiotto and Witten. We use the gravity duals to compute the one-point functions of some chiral operators in the N=4 SYM theory on a half-line at strong coupling, and find that they do not match with the expectation values of the same operators with the same boundary conditions at small 't Hooft coupling. Our solutions may also be interpreted as the gravity duals of 4d N=4 SYM on AdS_4, with various boundary conditions.