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Discrete Torsion, Covering Groups and Quiver Diagrams

Bo Feng·Amihay Hanany·Yang-Hui He·Nikolaos Prezas
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Abstract

Without recourse to the sophisticated machinery of twisted group algebras, projective character tables and explicit values of 2-cocycles, we here present a simple algorithm to study the gauge theory data of D-brane probes on a generic orbifold G with discrete torsion turned on. We show in particular that the gauge theory can be obtained with the knowledge of no more than the ordinary character tables of G and its covering group G*. Subsequently we present the quiver diagrams of certain illustrative examples of SU(3)-orbifolds which have non-trivial Schur Multipliers. The paper serves as a companion to our earlier work (arXiv:hep-th/0010023) and aims to initiate a systematic and computationally convenient study of discrete torsion.

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Bo Feng, Amihay Hanany, Yang-Hui He, Nikolaos Prezas. 2001-05-09. Discrete Torsion, Covering Groups and Quiver Diagrams. https://doi.org/10.1088/1126-6708%2F2001%2F04%2F037

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