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Twisted equivariant K-theory with complex coefficients

Daniel S. Freed·Michael J. Hopkins·Constantin Teleman
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Abstract

Using a global version of the equivariant Chern character, we describe the complexified twisted equivariant K-theory of a space with a compact Lie group action in terms of fixed-point data. We apply this to the case of a compact Lie group acting on itself by conjugation, and relate the result to the Verlinde algebra and to the Kac numerator at q=1. Verlinde's formula is also discussed in this context.

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Daniel S. Freed, Michael J. Hopkins, Constantin Teleman. 2006-07-23. Twisted equivariant K-theory with complex coefficients. https://doi.org/10.1112/jtopol%2Fjtm001

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