English

T-duality for circle bundles via noncommutative geometry

High Energy Physics - Theory 2014-12-05 v2 K-Theory and Homology Operator Algebras

Abstract

Recently Baraglia showed how topological T-duality can be extended to apply not only to principal circle bundles, but also to non-principal circle bundles. We show that his results can also be recovered via two other methods: the homotopy-theoretic approach of Bunke and Schick, and the noncommutative geometry approach which we previously used for principal torus bundles. This work has several interesting byproducts, including a study of the K-theory of crossed products by Isom(R), the universal cover of O(2), and some interesting facts about equivariant K-theory for Z/2. In the final section of this paper, these results are extended to the case of bundles with singular fibers, or in other words, non-free O(2)-actions.

Keywords

Cite

@article{arxiv.1306.4198,
  title  = {T-duality for circle bundles via noncommutative geometry},
  author = {Varghese Mathai and Jonathan Rosenberg},
  journal= {arXiv preprint arXiv:1306.4198},
  year   = {2014}
}

Comments

19 pages, minor corrections including typo fixes and added references

R2 v1 2026-06-22T00:35:54.317Z