Speaker:  Davide Gaiotto (Perimeter Institute for Theoretical Physics)

Abstract: The 't Hooft expansion is the key structure underlying dualities between gauge theories of large matrices and string theories. I will review categorical aspects of the 't Hooft expansion, matching the formal deformation space of certain ``fundamental modifications'' of the gauge theory to the formal deformation space of a category of boundary conditions ("D-branes") for a 2d dg-TFT, to be identified with the world-volume theory for the string theory. I will illustrate this by reviewing the holographic description of correlation functions for a 2d chiral algebra/VOA deforming H^*(gl_N[A[z]];gl_N) for a 2d CY algebra A.