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arXiv · 1510.05482

Exts and the AGT relations

Andrei Neguţ
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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.

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Andrei Neguţ. 2016-05-31. Exts and the AGT relations. https://doi.org/10.1007/s11005-016-0865-3

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