Exts and the AGT relations

Abstract

We prove the connection between the Nekrasov partition function of N=2 super-symmetric U(2) gauge theory with adjoint matter and conformal blocks for the Virasoro algebra, as predicted by the Alday-Gaiotto-Tachikawa relations. Mathematically, this is achieved by relating the Carlsson-Okounkov Ext vector bundle on the moduli space of rank 2 sheaves with Liouville vertex operators.Our approach is geometric in nature, and uses a new method for intersection-theoretic computations of the Ext operator.

minor modifications

References in corpus (1)

• Extended Conformal Symmetry and Recursion Formulae for Nekrasov Partition Function

Cited by in corpus (3)

• A slow review of the AGT correspondence
• Instanton R-matrix and W-symmetry
• Generalized Macdonald Functions on Fock Tensor Spaces and Duality Formula for Changing Preferred Direction