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arXiv · 2112.10227

Nonabelian Twists of the $D_4$ Theory

Jacques Distler·Behzat Ergun·Ali Shehper
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Abstract

We study theories of type $D_4$ in class-S, with nonabelian outer-automorphism twists around various cycles of the punctured Riemann surface $C$. We propose an extension of previous formul\ae\ for the superconformal index to cover this case and classify the SCFTs corresponding to fixtures (3-punctured spheres). We then go on to study families of SCFTs corresponding to once-punctured tori and 4-punctured spheres. These exhibit new behaviours, not seen in previous investigations. In particular, the generic theory with 4 punctures on the sphere from non-commuting $\mathbb{Z}_2$ twisted sectors has six distinct weakly-coupled descriptions.

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Jacques Distler, Behzat Ergun, Ali Shehper. 2021-12-19. Nonabelian Twists of the $D_4$ Theory. https://arxiv.org/abs/2112.10227

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