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Orbifold quantum cohomology of the classifying space of a finite group

Tyler J. Jarvis·Takashi Kimura
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Abstract

We work through, in detail, the orbifold quantum cohomology, with gravitational descendants, of the stack BG, the point modulo trivial action of a finite group G. We provide a simple description of algebraic structures on the state space of this theory. As a consequence, we find that multiple copies of commuting Virasoro algebras appear in this theory which completely determine the correlators of the theory.

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Tyler J. Jarvis, Takashi Kimura. 2002-05-01. Orbifold quantum cohomology of the classifying space of a finite group. https://arxiv.org/abs/math/0112037

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