Huijoon Sohn | Searcharxiv

arXiv2026

Non-unitary Haagerup-like TQFTs and RCFTs from generalized S-fold SCFTs

Building on earlier work by Gang, Kim, and Lee, we extend the known class of 3-dimensional non-unitary topological quantum field theories (TQFTs) and 2-dimensional non-unitary rational conformal field theories (RCFTs). The TQFTs are obtained by applying topological twist to generalized S-fold superconformal field theories (SCFTs). They are related to the RCFTs through the bulk-boundary correspondence. For certain families, we propose simple lines in the TQFTs, together with expressions for the characters and modular $S$ matrices of their associated boundary RCFTs. For broader family, we propose modular $S$ and $T$ matrices for the TQFTs. For particular members of this family, the resulting modular matrices are identified with the generalized Haagerup-Izumi modular matrices up to Galois conjugation.

hep-th↗

arXiv2025

Torus Knots and Minimal Models Revisited : Rational VOA characters from non-hyperbolic knots

In 2003, Hikami and Kirillov uncovered an intriguing connection between torus knots $\mathcal{K}_{(P,Q)}$ and Virasoro minimal models $\mathcal{M}(P,Q)$ by relating the Kashaev invariants of the knots to the characters of the corresponding minimal models. In this work, we recover and extend this connection by combining the 3D--3D correspondence with a bulk--boundary correspondence. More concretely, we study the 3D $\mathcal{N}=2$ gauge theories associated with torus-knot complements via the Dimofte--Gaiotto--Gukov construction and show that, in the infrared, these theories either flow to a unitary TQFT (when $|P-Q| = 1$), whose boundary chiral algebra reproduces that of the associated unitary minimal model, or to a 3D $\mathcal{N}=4$ rank-0 SCFT (when $|P-Q| > 1$), which realizes the corresponding non-unitary chiral minimal model at the boundary after an appropriate topological twist. This framework yields new Nahm-sum-like expressions for the characters of Virasoro minimal models and other related rational conformal field theories, providing a systematic algorithm for constructing characters of rational VOAs directly from the combinatorial data of an ideal triangulation of a non-hyperbolic knot complement.

hep-th↗