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Supersymmetric WZW models and twisted K-theory of SO(3)

Volker Braun·Sakura Schafer-Nameki
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Abstract

We present an encompassing treatment of D-brane charges in supersymmetric SO(3) WZW models. There are two distinct supersymmetric CFTs at each even level: the standard bosonic SO(3) modular invariant tensored with free fermions, as well as a novel twisted model. We calculate the relevant twisted K-theories and find complete agreement with the CFT analysis of D-brane charges. The K-theoretical computation in particular elucidates some important aspects of N=1 supersymmetric WZW models on non-simply connected Lie groups.

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Volker Braun, Sakura Schafer-Nameki. 2004-04-12. Supersymmetric WZW models and twisted K-theory of SO(3). https://arxiv.org/abs/hep-th/0403287

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