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arXiv · 1212.0545

2d TQFT structure of the superconformal indices with outer-automorphism twists

Noppadol Mekareeya·Jaewon Song·Yuji Tachikawa
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Abstract

We study the superconformal indices of 4d theories coming from 6d N=(2,0) theory of type Γon a Riemann surface, with the action of the outer-automorphism σin the trace. We find that the indices are given by the partition function of a deformed 2d Yang-Mills on the Riemann surface with gauge group G which is S-dual to the subgroup of Γfixed by σ. In the 2-parameter deformed version, we find that it is governed not by Macdonald polynomials of type G, but by Macdonald polynomials associated to twisted affine root systems.

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Noppadol Mekareeya, Jaewon Song, Yuji Tachikawa. 2012-12-03. 2d TQFT structure of the superconformal indices with outer-automorphism twists. https://doi.org/10.1007/jhep03(2013)171

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