Towards non-invertible anomalies from generalized Ising models

Abstract

We present a general approach to the bulk-boundary correspondence of noninvertible topological phases, including both topological and fracton orders. This is achieved by a novel bulk construction protocol where solvable (d+1)(d+1)-dimensional bulk models with noninvertible topology are constructed from the so-called generalized Ising (GI) models in dd dimensions. The GI models can then terminate on the boundaries of the bulk models. The construction generates abundant examples, including not only prototype ones such as \mathbb{Z}_2ℤ2 toric code models in any dimensions no less than two, and the X-cube fracton model, but also more diverse ones such as the \mathbb{Z}_2x \mathbb{Z}_2ℤ2xℤ2 topological order, the 4d \mathbb{Z}_2ℤ2 topological order with pure-loop excitations, etc. The boundary of the solvable model is potentially anomalous and corresponds to precisely only sectors of the GI model that host certain total symmetry charges and/or satisfy certain boundary conditions. We derive a concrete condition for such bulk-boundary correspondence. The condition is violated only when the bulk model is either trivial or fracton ordered. A generalized notion of Kramers-Wannier duality plays an important role in the construction. Also, utilizing the duality, we find an example where a single anomalous theory can be realized on the boundaries of two distinct bulk fracton models, a phenomenon not expected in the case of topological orders. More generally, topological orders may also be generated starting with lattice models beyond the GI models, such as those with symmetry protected topological orders, through a variant bulk construction, which we provide in an appendix.

A Chern-Simons theory for dipole symmetry

“…Similar observations have been made in a recent work about subsystem anomaly[56]. In the meantime, it was noticed that a single boundary anomaly may correspond to different bulk fracton models[57][58][59].…”

Emergent (2+1)D topological orders from iterative (1+1)D gauging

“…The questions of how our construction can be generalized to non-Abelian topological orders and its connection with Ref. [37] remain open. Finally, in a forthcoming paper [38], we will present the emergence of non-trivial (3+1)D phases from the gauging of (2+1)D symmetries.…”

“…I thank David Blanik for the discussion that inspired this work, Bram Vancraeynest-De Cuiper, Aleksander Kubicki, Anasuya Lyons and Isabel Miranda for their helpful comments on the manuscript and Dominic Williamson for pointing out Ref. [37].…”

Symmetry TFT for subsystem symmetry

“…Finally, subsystem SymTFT provides a bulk-boundary point of view to study subsystem symmetry. Recently, there are other efforts to study fracton models from bulk-boundary correspondence [82][83][84][85]. Subsystem SymTFT also provides hints to study fracton statistics [86,87].…”