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Algebra and Geometry Seminar

Monday, March 2, 2020
4:00pm to 5:00pm
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Linde Hall 387
Cluster structure on K-theoretic Coulomb branches
Alexander Shapiro, Department of Mathematics, UC Berkeley,

Braverman, Finkelberg, and Nakajima define the K-theoretic Coulomb branch of a 3d N=4 SUSY gauge theory as the affine variety M_{G,N} arising as the equivariant K-theory of certain moduli space R_{G,N}, labelled by the complex reductive group G and its complex representation N. It was conjectured by Gaiotto, that (quantized) K-theoretic Coulomb branches bear the structure of (quantum) cluster varieties. I will outline a proof of this conjecture for quiver gauge theories, provided that the quiver does not have loops, and show how the cluster structure allows to count the BPS states (aka DT-invariants) of the theory. Time permitting, I will also show how the above cluster structure relates to positive and Gelfand-Tsetlin representations of quantum groups, and higher rank Fenchel–Nielsen coordinates on moduli spaces of PGL_n local systems. This talk is based on joint works with Gus Schrader.

For more information, please contact Math Department by phone at 626-395-4335 or by email at [email protected].