Comparing $h$-genera, Bridge-1 genera and Heegaard genera of knots
Geometric Topology
2025-04-29 v1
Abstract
Let , , , be the -genus, Heegaard genus, bridge-1 genus, tunnel number of a knot in the -sphere , respectively. It is known that . A natural question arises: when do these invariants become equal? We provide the necessary and sufficient conditions for equality and use these to show that for each integer , the following three families of knots are infinite: \begin{eqnarray} A_{n}=\{K\mid t(K)=n<g_1(K)\}, B_{n}=\{K\mid g_1(K)=n<h(K)\}, C_{n}=\{K\mid h(K)=n<g_H(K)\}. \end{eqnarray} This result resolves a conjecture in \cite{Mo2}, confirming that each of these families is infinite.
Cite
@article{arxiv.2504.19118,
title = {Comparing $h$-genera, Bridge-1 genera and Heegaard genera of knots},
author = {Ruifeng Qiu and Chao Wang and Yanqing Zou},
journal= {arXiv preprint arXiv:2504.19118},
year = {2025}
}
Comments
comments are welcome