2013/07/31 by Ilka Brunner, Nils Carqueville, Daniel Plencner · 1 citation
Physics and Astronomy · Mathematics · #hep-th #math-ph #math.MP #math.QA
paper · pdf · doi:10.1007/s00220-014-2056-3
published as Comm. Math. Phys. 332 (2014), 669-712 · 54 pages; v2: minor changes
arxiv created 2014/06/02 · arxiv updated 2014/09/16
We study orbifolds of two-dimensional topological field theories using defects. If the TFT arises as the twist of a superconformal field theory, we recover results on the Neveu-Schwarz and Ramond sectors of the orbifold theory as well as bulk-boundary correlators from a novel, universal perspective. This entails a structure somewhat weaker than ordinary TFT, which however still describes a sector of the underlying conformal theory. The case of B-twisted Landau-Ginzburg models is discussed in detail, where we compute charge vectors and superpotential terms for B-type branes. Our construction also works in the absence of supersymmetry and for generalised "orbifolds" that need not arise from symmetry groups. In general this involves a natural appearance of Hochschild (co)homology in a 2-categorical setting, in which among other things we provide simple presentations of Serre functors and a further generalisation of the Cardy condition.