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arXiv · 2403.00053

Localization and resummation of unstable instantons in 2d Yang-Mills

Luca Griguolo·Rodolfo Panerai·Jacopo Papalini·Domenico Seminara·Itamar Yaakov
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Abstract

We compute the exact all-orders perturbative expansion for the partition function of 2d $\mathrm{SU}(2)$ Yang-Mills theory on closed surfaces around higher critical points. We demonstrate that the expansion can be derived from the lattice partition function for all genera using a distributional generalization of the Poisson summation formula. We then recompute the expansion directly, using a stationary phase version of supersymmetric localization. The result of localization is a novel effective action which is itself a distribution rather than a function of the supersymmetric moduli. We comment on possible applications to A-twisted models and their analogs in higher dimensions.

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Luca Griguolo, Rodolfo Panerai, Jacopo Papalini, Domenico Seminara, Itamar Yaakov. 2024-02-29. Localization and resummation of unstable instantons in 2d Yang-Mills. https://arxiv.org/abs/2403.00053

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