T-branes through 3d mirror symmetry

TL;DR

This paper uses 3d mirror symmetry to reveal how T-branes, exotic D-brane states with non-commuting scalars, deform M2-brane superpotentials and alter gauge theory moduli spaces in M-theory.

Contribution

It introduces a novel framework employing 3d mirror symmetry to understand T-branes in M-theory, revealing new N=2 quiver gauge theories with unique Coulomb branch structures.

Findings

T-branes deform M2-brane superpotentials with monopole operators.

They partially break flavor symmetry and reduce supersymmetry from N=4 to N=2.

New N=2 quiver gauge theories with distinct Coulomb branches are uncovered.

Abstract

T-branes are exotic bound states of D-branes, characterized by mutually non-commuting vacuum expectation values for the worldvolume scalars. The M/F-theory geometry lifting D6/D7-brane configurations is blind to the T-brane data. In this paper, we make this data manifest, by probing the geometry with an M2-brane. We find that the effect of a T-brane is to deform the membrane worldvolume superpotential with monopole operators, which partially break the three-dimensional flavor symmetry, and reduce supersymmetry from N=4 to N=2. Our main tool is 3d mirror symmetry. Through this language, a very concrete framework is developed for understanding T-branes in M-theory. This leads us to uncover a new class of N=2 quiver gauge theories, whose Higgs branches mimic those of membranes at ADE singularities, but whose Coulomb branches differ from their N=4 counterparts.