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arXiv · 1512.05388

BPS/CFT correspondence: non-perturbative Dyson-Schwinger equations and qq-characters

Nikita Nekrasov
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Abstract

We study symmetries of quantum field theories involving topologically distinct sectors of the field space. To exhibit these symmetries we define special gauge invariant observables, which we call the $qq$-characters. In the context of the BPS/CFT correspondence, using these observables, we derive an infinite set of Dyson-Schwinger-type relations. These relations imply that the supersymmetric partition functions in the presence of $Ω$-deformation and defects obey the Ward identities of two dimensional conformal field theory and its $q$-deformations. The details will be discussed in the companion papers.

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Nikita Nekrasov. 2016-01-02. BPS/CFT correspondence: non-perturbative Dyson-Schwinger equations and qq-characters. https://doi.org/10.1007/jhep03(2016)181

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