Nikita Nekrasov (Stony Brook), “Super-spin-chains and gauge theories”
ABSTRACT: Bethe/gauge correspondence relates quantum integrable systems to supersymmetric gauge theories. One of the mathematical consequences of this relation is the identification of the quantum cohomology ring of certain varieties with Bethe subalgebras of quantum algebras. In this talk the two dimensional gauge theories corresponding to the Yangians of super-algebras of A type will be described. In a parallel development … Read More
Yaim Cooper (Harvard), “Severi degrees via representation theory”
ABSTRACT: The Severi degrees of P1XP1 can be computed in terms of an explicit operator on the Fock space F[P1]. We will discuss this approach and will also describe several further applications. We will discuss using Fock spaces to compute relative Gromov-Witten theory of other surfaces, such as Hirzebruch surfaces and EXP1. We will also discuss operators which calculate descendants. … Read More
Penka Georgieva (Institut de Mathématiques de Jussieu), “The local real Gromov-Witten theory of curves”
ABSTRACT: The local Gromov-Witten theory of curves studied by Bryan and Pandharipande revealed strong structural results for the local GW invariants, which were later used by Ionel and Parker in the proof of the Gopakumar-Vafa conjecture. In this talk I will report on a joint work in progress with Eleny Ionel on the extension of these results to the real … Read More
Pavel Etingof (MIT), “Cyclotomic Double affine Hecke algebras and multiplicative quiver varieties”
ABSTRACT: I’ll show that the partially spherical cyclotomic rational Cherednik algebra (obtained from the full rational Cherednik algebra by averaging out the cyclotomic part of the underlying reflection group) has four other descriptions: (1) as a subalgebra of the degenerate DAHA of type A given by generators; (2) as an algebra given by generators and relations; (3) as an algebra … Read More
Ron Donagi (University of Pennsylvania), “Non-Abelian Hodge Theory, Mirror Symmetry, and Geometric Langlands”
ABSTRACT: We will review the Geometric Langlands Conjecture, a non-abelian generalization of the theory of curves and their Jacobians. We will compare it to its arithmetic variants and discuss its overlap with homological mirror symmetry. We will then outline our program for proving GLC using non Abelian Hodge theory and Hitchin’s system. Finally, we will describe some recent results on … Read More
Hiraku Nakajima (Kavli IPMU), “Coulomb branches and their resolutions”
ABSTRACT: Coulomb branch of a 3d gauge theory is defined (after Braverman-Finkelberg-N) as the spectrum of a certain commutative ring, defined as a convolution algebra of a certain infinite dimensional variety. A variant of its definition gives a (partial) resolution, when we have the so-called flavor symmetry in the theory. We identify the resolution with smooth Cherkis bow variety for … Read More
Alexander Givental (UC Berkeley), “The adelic Hirzebruch-RR in higher genus quantum K-theory”
ABSTRACT: I will explain how the problem of expressing K-theoretic Gromov-Witten invariants in terms of cohomological ones leads to an elegant quantum-mechanical formula.
Georg Oberdieck (MIT), “Rational curves in the Fano variety of lines via Gromov-Witten theory”
ABSTRACT: I will explain how to use Gromov-Witten theory to classify all rational curves with primitive curve class on the Fano variety of lines in a very general cubic fourfold. Joint work with Junliang Shen and Qizheng Yin.
Ciprian Manolescu (UCLA) “GPV invariants and Dehn surgery”
Gukov, Putrov and Vafa postulated the existence of some 3-manifold invariants, obtained by counting BPS states in the 3d N=2 theory T[M_3]. The GPV invariants take the form of power series converging in the unit disk, and whose radial limits at the roots of unity give the Witten-Reshetikhin-Turaev invariants. Furthermore, these power series have integer coefficients, and should admit a … Read More
Sabin Cautis (University of Britsh Columbia) “Exotic t-structure constructions using quantum affine algebras”
We explain how quantum affine algebras can be used to systematically construct “exotic” t-structures. One of the application is to obtain exotic t-structures on certain convolution varieties defined using affine Grassmannians (these varieties play an important role in the geometric Langlands program, knot homology constructions, the coherent Satake category etc.) As a special case we also recover the exotic t-structures … Read More