activity
20242026
collaborators

9 papers

math.QA2026

String nets for twisted pivotal categories

Benjamin Haïoun, William Stewart, Filippos Sytilidis

We develop a graphical calculus for monoidal categories equipped with twisted pivotal structures, which are a generalization of pivotal structures originating from the study of ori…

math.GT2026

Skein (3+1)-TQFTs from Non-Semisimple Ribbon Categories

Francesco Costantino, Nathan Geer, Benjamin Haïoun +1

We define a (3+1)-TQFT associated with possibly non-semisimple finite unimodular ribbon tensor categories using skein theory. This gives an explicit realization of a TQFT predicted…

math.QA2026

Graded spherical skein 2+1-G-HQFT and modified Turaev-Viro invariants

Francesco Costantino, Nathan Geer, Benjamin Haïoun +1

For G a group, we present a G-graded version of chromatic maps and skein modules and use them to define a 2+1-G-HQFT out of a G-chromatic category. The construction applies to the…

math.QA2026

Skein Categories in Non-semisimple Settings

Jennifer Brown, Benjamin Haïoun

We introduce a version of skein categories of surfaces which depends on a tensor ideal in a linear ribbon category, thereby extending the existing theory to the setting of non-semi…

math.GT2026

Defining extended TQFTs via handle attachments

Benjamin Haïoun

We give a finite presentation of the cobordism symmetric monoidal bicategory of (smooth, oriented) closed manifolds, cobordisms and cobordisms with corners as an extension of the b…

math.QA2025

Invariants of 4-Dimensional 2-Handlebodies from the Temperley-Lieb Category in Positive Characteristic

Thibault D. Décoppet, Benjamin Haïoun

We investigate invariants of 4-dimensional 2-handlebodies associated to the Temperley-Lieb category in characteristic and at a primitive fourth root of unity. These invariant…