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arXiv · 1302.5425

Generalised Moonshine and Holomorphic Orbifolds

Matthias R. Gaberdiel·Daniel Persson·Roberto Volpato
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Abstract

Generalised moonshine is reviewed from the point of view of holomorphic orbifolds, putting special emphasis on the role of the third cohomology group H^3(G, U(1)) in characterising consistent constructions. These ideas are then applied to the case of Mathieu moonshine, i.e. the recently discovered connection between the largest Mathieu group M_24 and the elliptic genus of K3. In particular, we find a complete list of twisted twining genera whose modular properties are controlled by a class in H^3(M_24, U(1)), as expected from general orbifold considerations.

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Matthias R. Gaberdiel, Daniel Persson, Roberto Volpato. 2013-02-21. Generalised Moonshine and Holomorphic Orbifolds. https://arxiv.org/abs/1302.5425

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