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Related papers: Crosscap number and knot projections

200 papers

Traditionally, knot theorists have considered projections of knots where there are two strands meeting at every crossing. A multi-crossing is a crossing where more than two strands meet at a single point, such that each strand bisects the…

Geometric Topology · Mathematics 2018-05-14 Daishiro Nishida

We study the 3-dimensional immersed crosscap number of a knot, which is a nonorientable analogue of the immersed Seifert genus. We study knots with immersed crosscap number 1, and show that a knot has immersed crosscap number 1 if and only…

Geometric Topology · Mathematics 2020-04-29 Mark C. Hughes , Seungwon Kim

We prove that for 2-bridge knots, the diameter, D, of the set of boundary slopes is twice the crossing number, c. This constitutes partial verification of a conjecture that, for all knots in S^3, D is at most 2c.

Geometric Topology · Mathematics 2007-05-23 Thomas W. Mattman , Gabriel Maybrun , Kristin Robinson

An upper bound of the superbridge index of the connected sum of two knots is given in terms of the braid index of the summands. Using this upper bound and minimal polygonal presentations, we give an upper bound in terms of the superbridge…

Geometric Topology · Mathematics 2007-05-23 Gyo Taek Jin

The ropelength of a knot is the minimum length required to tie it. Computational upper bounds have previously been computed for every prime knot with up to 11 crossings. Here, we present ropelength measurements for the 2176 knots with 12…

Geometric Topology · Mathematics 2023-06-01 Alexander R. Klotz , Caleb J. Anderson

Families of alternating knots (links) and tangles are studied using as building block the conway defined as the twisting of two strands. The regular representation of knots assumes the projection has the minimal number of overpassings, and…

General Topology · Mathematics 2012-06-18 E. Piña

In this paper, we show the trivializing number of all minimal diagrams of positive 2-bridge knots and study the relation between the trivializing number and the unknotting number for a part of these knots.

Geometric Topology · Mathematics 2016-02-24 Kazuhiko Inoue

We explore the application of automated reasoning techniques to unknot detection, a classical problem of computational topology. We adopt a two-pronged experimental approach, using a theorem prover to try to establish a positive result…

Logic in Computer Science · Computer Science 2014-05-19 Andrew Fish , Alexei Lisitsa

This paper investigates the relationship between the signature and the crossing number of knots and links. We refine existing theorems and provide a comprehensive classification of links with specific properties, particularly those with…

Geometric Topology · Mathematics 2024-10-02 Kai Ishihara , Kei Okada , Koya Shimokawa

We study symmetric crossing change operations for strongly invertible knots. Our main theorem is that the most natural notion of equivariant unknotting number is not additive under connected sum, in contrast with the longstanding conjecture…

Geometric Topology · Mathematics 2025-02-14 Keegan Boyle , Wenzhao Chen

The list of knots with up to 10 crossings is commonly referred to as the Rolfsen Table. This paper presents a way to generate the Rolfsen table in a simple, clear, and reproducible manner. The methods we use are similar to those used by J.…

Geometric Topology · Mathematics 2017-05-31 Andrey Boris Khesin

Experimental data from Dunfield et al using random grid diagrams suggests that the genus of a knot grows linearly with respect to the crossing number. Using billiard table diagrams of Chebyshev knots developed by Koseleff and Pecker and a…

Geometric Topology · Mathematics 2021-08-03 Moshe Cohen

A long standing open conjecture states that if a link $\mathcal{K}$ is alternating, then its ropelength $L(\mathcal{K})$ is at least of the order $O(Cr(\mathcal{K}))$. A recent result shows that the maximum braid index of a link bounds the…

Geometric Topology · Mathematics 2021-08-25 Yuanan Diao

We study the band-unknotting number $u_{nb}(K)$ of a knot $K$, and how it behaves with respect to connect sums. We show that this sub-additive function is not additive under connected sums, by finding infinitely many examples of knots $K_1,…

Geometric Topology · Mathematics 2025-12-09 Nakisa Ghanbarian , Stanislav Jabuka

In this paper, we give the trivializing number of all minimal diagrams of positive 2-bridge knots, and study the relation between the trivializing number and the unknotting number for a part of these knots.

K-Theory and Homology · Mathematics 2015-12-08 Kazuhiko Inoue

We answer a question posed by Fielder in [1] concerning two notions of crossing number for algebraic knots $K$ under Hopf fibration, one topological, denoted $h(K)$, the other coming from the realization of such knots around complex…

Geometric Topology · Mathematics 2020-06-30 Maciej Mroczkowski

We introduce the notion of slice depth of a 2-knot K, which is the minimal integer n such that K is n-slice. We give an upper bound for the slice depth of the n-twist spin of a classical knot which belongs to several specific classes,…

Geometric Topology · Mathematics 2025-09-24 Ayaka Ise

A rational knot or link can be put into a standard alternating format which has horizontal and vertical twist sites (double helices). The number and type of these twist sites are determined by terms of next-to-highest $z$-degree in…

Geometric Topology · Mathematics 2014-10-02 Mark E. Kidwell , Kerry M. Luse

Generalizing Howie and Greene's characterization of alternating knots, we give a topological characterization of almost alternating knots.

Geometric Topology · Mathematics 2017-01-30 Tetsuya Ito

This paper is devoted to prove the existence of $q$-periodic alternating projections of prime alternating $q$-periodic knots. The main tool is the Menasco-Thistlethwaite's Flyping theorem. Let $K$ be an oriented prime alternating knot that…

Geometric Topology · Mathematics 2021-03-08 Antonio F. Costa , Cam Van Quach Hongler