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arXiv · 2010.04590

Real K-theories

Max Karoubi
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Abstract

The purpose of this short paper is to investigate relations between various real K-theories. In particular, we show how a real projective bundle theorem implies an unexpected relation between Atiyah's KR-theory and the usual equivariant K-theory of real vector bundles. This relation has been used recently in a new computation of the Witt group of real curves by Schlichting, Weibel and the author. We also interpret Atiyah's theory as a special case of twisted K-theory.

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Max Karoubi. 2020-10-09. Real K-theories. https://arxiv.org/abs/2010.04590

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