From Torus Bundles to Particle-Hole Equivariantization
arXiv:2106.01959 · doi:10.1007/s11005-022-01508-3
Abstract
We continue the program of constructing (pre)modular tensor categories from 3-manifolds first initiated by Cho-Gang-Kim using theory in physics and then mathematically studied by Cui-Qiu-Wang. An important structure involved is a collection of certain characters on a given manifold which serve as the simple object types in the corresponding category. Chern-Simons invariants and adjoint Reidemeister torsions play a key role in the construction, and they are related to topological twists and quantum dimensions, respectively, of simple objects. The modular -matrix is computed from local operators and follows a trial-and-error procedure. It is currently unknown how to produce data beyond the modular - and -matrices. There are also a number of subtleties in the construction which remain to be solved. In this paper, we consider an infinite family of 3-manifolds, that is, torus bundles over the circle. We show that the modular data produced by such manifolds are realized by the -equivariantization of certain pointed premodular categories. Here the equivariantization is performed for the -action sending a simple (invertible) object to its inverse, also called the particle-hole symmetry. It is our hope that this extensive class of examples will shed light on how to improve the program to recover the full data of a premodular category.
16 pages, minor changes, to appear in Lett Math Phys