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arXiv · 2106.07670

BPS Indices, Modularity and Perturbations in Quantum K-theory

Hans Jockers·Peter Mayr·Urmi Ninad·Alexander Tabler
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Abstract

We study a perturbation family of N=2 3d gauge theories and its relation to quantum K-theory. A 3d version of the Intriligator-Vafa formula is given for the quantum K-theory ring of Grassmannians. The 3d BPS half-index of the gauge theory is connected to the theory of bilateral hypergeometric q-series, and to modular q-characters of a class of conformal field theories in a certain massless limit. Turning on 3d Wilson lines at torsion points leads to mock modular behavior. Perturbed correlators in the IR regime are computed by determining the UV-IR map in the presence of deformations.

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Hans Jockers, Peter Mayr, Urmi Ninad, Alexander Tabler. 2021-06-14. BPS Indices, Modularity and Perturbations in Quantum K-theory. https://doi.org/10.1007/jhep02(2022)044

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