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Thom isomorphism and Push-forward map in twisted K-theory

Alan L. Carey·Bai-Ling Wang
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Abstract

We establish the Thom isomorphism in twisted K-theory for any real vector bundle and develop the push-forward map in twisted K-theory for any differentiable proper map $f: X\to Y$ (not necessarily K-oriented). The push-forward map generalizes the push-forward map in ordinary K-theory for any $K$-oriented differentiable proper map and the Atiyah-Singer index theorem of Dirac operators on Clifford modules. For $D$-branes satisfying Freed-Witten's anomaly cancellation condition in a manifold with a non-trivial $B$-field, we associate a canonical element in the twisted K-group to get the so-called D-brane charges.

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Alan L. Carey, Bai-Ling Wang. 2006-07-12. Thom isomorphism and Push-forward map in twisted K-theory. https://arxiv.org/abs/math/0507414

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