Unoriented WZW Models and Holonomy of Bundle Gerbes
arXiv:hep-th/0512283 · doi:10.1007/s00220-007-0271-x
Abstract
The Wess-Zumino term in two-dimensional conformal field theory is best understood as a surface holonomy of a bundle gerbe. We define additional structure for a bundle gerbe that allows to extend the notion of surface holonomy to unoriented surfaces. This provides a candidate for the Wess-Zumino term for WZW models on unoriented surfaces. Our ansatz reproduces some results known from the algebraic approach to WZW models.
46 pages, 9 figures. Version 2 contains corrected proofs of Lemma 2 and Theorem 1, and an improved discussion of the WZW bundle gerbe