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arXiv · 2202.10501

Localizing non-linear ${\cal N}=(2,2)$ sigma model on $S^2$

Victor Alekseev·Guido Festuccia·Victor Mishnyakov·Nicolai Terziev·Maxim Zabzine
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Abstract

We present a systematic study of ${\cal N}=(2,2)$ supersymmetric non-linear sigma models on $S^2$ with the target being a K\"ahler manifold. We discuss their reformulation in terms of cohomological field theory. In the cohomological formulation we use a novel version of 2D self-duality which involves a $U(1)$ action on $S^2$. In addition to the generic model we discuss the theory with target space equivariance corresponding to a supersymmetric sigma model coupled to a non-dynamical supersymmetric background gauge multiplet. We discuss the localization locus and perform a one-loop calculation around the constant maps. We argue that the theory can be reduced to some exotic model over the moduli space of holomorphic disks.

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Victor Alekseev, Guido Festuccia, Victor Mishnyakov, Nicolai Terziev, Maxim Zabzine. 2022-02-21. Localizing non-linear ${\cal N}=(2,2)$ sigma model on $S^2$. https://doi.org/10.1140/epjc/s10052-022-10610-8

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