# (02.06.) Probing T-branes with 3d mirror symmetry

Andres Collinucci (Brussels)

02.06.2016 at 16:15

M-theory on spacetimes with ADE singularities gives rise to gauge theories with ADE gauge groups. The case of the An singularity reduces to a IIA stack of (n+1) D6-branes. Crucially, this picture is incomplete at best. For instance, D6-branes can form bound states, known as "T-branes”, by Higgsing the worldvolume scalar with a nilpotent vev. Contrary to more familiar setups, the D6-branes are not being separated, and in M-theory the singularity is not being resolved or deformed. Yet, the gauge group gets broken to a subgroup. How are such effects encoded in M-theory? More broadly, can we really see all known D-branes when we uplift to M- theory? In this talk, I will introduce this issue, and present the results of a collaboration with Giacomelli, Savelli and Valandro, where we address this question by probing M-theory singularities with an M2-brane. Our main tool for understanding T-branes will be N=2 3d mirror symmetry. We will see that the M-theory uplift to T- branes are coherent states of light M2-branes wrapping vanishing cycles. These will manifest themselves as monopole operators in the probe theory. We will study the effective theory of the probe in these exotic backgrounds, and see that they can be described by ADE quivers where some nodes have been removed. These constitute a new class of N=2 3d gauge theories.

Arnold Sommerfeld Center

Theresienstrasse 37

Room 348