Ruifeng Qiu

collaborators

2 papers

math.GT2025

Comparing $h$ -genera, Bridge-1 genera and Heegaard genera of knots

Ruifeng Qiu, Chao Wang, Yanqing Zou

Let $h (K)$ , $g_{H} (K)$ , $g_{1} (K)$ , $t (K)$ be the $h$ -genus, Heegaard genus, bridge-1 genus, tunnel number of a knot $K$ in the $3$ -sphere $S^{3}$ , respectively. It is known that $g_H(K)…

math.GT2024

A lower bound of the crossing number of composite knots

Ruifeng Qiu, Chao Wang

Let $c (K)$ denote the crossing number of a knot $K$ , and let $K_{1} # K_{2}$ denote the connected sum of two oriented knots $K_{1}$ and $K_{2}$ . As a famous old question in knot theory, whe…

Comparing h-genera, Bridge-1 genera and Heegaard genera of knots

A lower bound of the crossing number of composite knots

Comparing $h$ -genera, Bridge-1 genera and Heegaard genera of knots