activity
20242026
collaborators

5 papers

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.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…

math.QA2025

Higher tensor categories and their extensions: notes from the Scottish Talbot On Algebra and Topology

Diogo Andrade, Julia Bierent, Jennifer Brown +28

These lecture notes are the product of a week-long learning workshop on the work of Johnson-Freyd and Reutter on the problem of the existence of minimal nondegenerate extensions of…

math.QA2025

Non-semisimple WRT at the boundary of Crane-Yetter

Benjamin Haïoun

We prove the slogan, promoted by Walker and Freed-Teleman twenty years ago, that "The Witten-Reshetikhin-Turaev 3-TQFT is a boundary condition for the Crane-Yetter 4-TQFT" and gene…

math.GT2024

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…