Gerbes over Orbifolds and Twisted K-theory

Ernesto Lupercio; Bernardo Uribe

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arXiv · math/0105039

Gerbes over Orbifolds and Twisted K-theory

Ernesto Lupercio·Bernardo Uribe

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Abstract

In this paper we construct an explicit geometric model for the group of gerbes over an orbifold $X$. We show how from its curvature we can obtain its characteristic class in $H^3(X)$ via Chern-Weil theory. For an arbitrary gerbe $\LL$, a twisting $\Korb{\LL}(X)$ of the orbifold $K$-theory of $X$ is constructed, and shown to generalize previous twisting by Rosenberg, Witten, Atiyah-Segal and Bowknegt et. al. in the smooth case and by Adem-Ruan for discrete torsion on an orbifold.

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BibTeX RIS

Ernesto Lupercio, Bernardo Uribe. 2002-03-19. Gerbes over Orbifolds and Twisted K-theory. https://arxiv.org/abs/math/0105039

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