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arXiv · 2310.06064

Equivariant Topological T-Duality

Tom Dove·Thomas Schick
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Abstract

Topological T-duality is a relationship between pairs (E, P ) over a fixed space X, where E over X is a principal torus bundle and P over E is a twist, such as a gerbe of principal PU(H)-bundle. This is of interest to topologists because of the T-duality transformation: a T-duality relation between pairs (E, P ) and (F, Q ) comes with an isomorphism (with degree shift) between the twisted K-theory of E and the twisted K-theory of F. We formulate topological T-duality in the equivariant setting, following the definition of Bunke, Rumpf, and Schick. We define the T-duality transformation in equivariant K-theory and show that it is an isomorphism for actions of compact Lie groups, equal to its own inverse and uniquely characterized by naturality and a normalization for trivial situations.

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Tom Dove, Thomas Schick. 2023-10-09. Equivariant Topological T-Duality. https://doi.org/10.1007/s00220-024-05044-0

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