Instantons on D7 brane probes and AdS/CFT with flavour

TL;DR

This paper reviews how instanton configurations on D7 brane probes in AdS/CFT relate to the Higgs branch and phase transitions, revealing insights into meson spectra, Bose-Einstein condensation, and thermal phase behavior.

Contribution

It introduces instanton configurations on D7 branes as a novel way to study the Higgs branch and phase transitions in the AdS/CFT framework with flavor.

Findings

Instantons generate a flow in the meson spectrum.

The Higgs branch is lifted by a potential in non-supersymmetric backgrounds.

Configurations model Bose-Einstein condensation and thermal phase transitions.

Abstract

Recent work on adding flavour to the generalized AdS/CFT correspondence is reviewed. In particular, we consider instanton configurations on two coincident D7 brane probes. These are matched to the Higgs branch of the dual field theory. In AdS_5 x S^5, the instanton generates a flow of the meson spectrum. For non-supersymmetric gravity backgrounds, the Higgs branch is lifted by a potential, which has non-trivial physical implications. In particular these configurations provide a gravity dual description of Bose-Einstein condensation and of a thermal phase transition.