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A-Genus and the Sigma Model

Kelly Jay Davis
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Abstract

This set of lecture notes presents a pedantic derivation of the connection between the $ {\hat A} $-genus of spacetime's loop space and the genus one partition function of the $ N=1/2 $ sigma model. It concludes with some remarks on possible generalizations of the $ {\hat A} $-genus which follow naturally from the `stringy' point-of-view but have yet to be explored mathematically. This set of lecture notes is geared towards a mathematical audience unfamiliar with the $ N=1/2 $ sigma model.

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Kelly Jay Davis. 1994-06-04. A-Genus and the Sigma Model. https://arxiv.org/abs/hep-th/9406023

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