Centrala begrepp
Computing the genus defect in Hopf arborescent links is decidable.
Sammanfattning
The article explores the decidability of computing the genus defect in a class of knots and links known as Hopf arborescent links. It discusses the structure of these links obtained from plumbings of Hopf bands, showing that their 4-dimensional invariants can be determined. The study focuses on Seifert surfaces and minor theory to establish well-quasi-orders for these surfaces. The construction process involves plane trees and iterative plumbings, leading to fibred surfaces with minimal genus. The paper also delves into related work on arborescent knots and general plumbing structures, highlighting the unique properties of Hopf arborescent links.
Statistik
Computing the genus defect in Hopf arborescent links is decidable.
Seifert surfaces form a well-quasi-order under a relation of minors.
Homeomorphic embeddings between plane trees establish surface-minor relations.
Kruskal Tree Theorem applies to well-quasi-ordering of Hopf arborescent links.
Citat
"The goal of this paper is to investigate the structure of a particular class of links, which we call Hopf arborescent links, in order to prove the decidability of some of their 4-dimensional invariants."
"Our main result is the following: For any fixed k, deciding whether an Hopf arborescent link L has genus defect at most k is decidable."
"While the algorithms behind Theorem 1.1 are not explicit, we would like to offer three reasons to motivate our results."