English

Embedded surface invariants via the Broda-Petit construction

Quantum Algebra 2025-11-11 v4 Geometric Topology

Abstract

We recall Petit's construction of "dichromatic" invariants of 4-manifolds computed from Kirby diagrams using a nested pair of ribbon fusion categories BC B \subset C as initial data. Along the way we prove a lemma that fits the use of formal linear combinations of simple objects with quantum dimensions a coefficients as in the constructions of Reshetikhin-Turaev, Broda, and Petit more firmly in the functorial framework favored by the authors. We then show that Hughes et al.'s banded-link presentations of surfaces embedded in 4-manifolds provide a means whereby Frobenius algebra in BB together with a suitable module over it lying in CC, give rise to an invariant of a surface-4-manifold pair. We provide a class of examples of suitable initial data and compute sufficient examples to show the invariant is sensitive to both genus and knotting.

Keywords

Cite

@article{arxiv.2303.11380,
  title  = {Embedded surface invariants via the Broda-Petit construction},
  author = {Ik Jae Lee and David N Yetter},
  journal= {arXiv preprint arXiv:2303.11380},
  year   = {2025}
}
R2 v1 2026-06-28T09:24:55.883Z