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arXiv · 1504.03284

K-Theory for Real C*-algebras via Unitary Elements with Symmetries

Jeffrey L. Boersema·Terry A. Loring
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Abstract

We prove that all eight KO groups for a real C*-algebra can be constructed from homotopy classes of unitary matrices that respect a variety of symmetries. In this manifestation of the KO groups, all eight boundary maps in the 24-term exact sequence associated to an ideal in a real C*-algebra can be computed as exponential or index maps with formulas that are nearly identical to the complex case.

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BibTeXRIS

Jeffrey L. Boersema, Terry A. Loring. 2015-04-13. K-Theory for Real C*-algebras via Unitary Elements with Symmetries. https://arxiv.org/abs/1504.03284

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