English
Related papers

Related papers: Alternating knots with unknotting number one

200 papers

In this paper we use artificial neural networks to predict and help compute the values of certain knot invariants. In particular, we show that neural networks are able to predict when a knot is quasipositive with a high degree of accuracy.…

Geometric Topology · Mathematics 2016-10-19 Mark C. Hughes

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 present a sequence of link invariants, defined from twisted Alexander polynomials, and discuss their effectiveness in distinguish knots. In particular, we recast and extend by geometric means a recent result of Silver and…

Geometric Topology · Mathematics 2018-12-24 Stefan Friedl , Stefano Vidussi

We determine a simple condition on a particular state graph of an alternating knot or link diagram that characterizes when the unoriented genus and crosscap number coincide, extending work of Adams and Kindred. Building on this same work…

Geometric Topology · Mathematics 2025-08-07 Moshe Cohen , Thomas Kindred , Adam M. Lowrance , Patrick D. Shanahan , Cornelia A. Van Cott

The algebraic unknotting number u_a(K) of a knot K was introduced by Hitoshi Murakami. It equals the minimal number of crossing changes needed to turn K into an Alexander polynomial one knot. In a previous paper the authors used the…

Geometric Topology · Mathematics 2013-08-29 Maciej Borodzik , Stefan Friedl

We explore under what conditions one can obtain a nontrivial knot, given a collection of $n$ vectors. First, we show how to get a crossing from any 3 vectors equal in magnitude, by arbitrarily picking 2 vectors and identifying the…

Geometric Topology · Mathematics 2016-12-21 Joseph Borgatti

The paper introduces Slope Conjecture which relates the degree of the Jones polynomial of a knot and its parallels with the slopes of incompressible surfaces in the knot complement. More precisely, we introduce two knot invariants, the…

Geometric Topology · Mathematics 2010-05-26 Stavros Garoufalidis

A weaving knot is an alternating knot whose minimal diagram is a closed braid of a lattice-like pattern. In this paper, the warping degree of a braid diagram is defined, and upper bounds of the unknotting number and the region unknotting…

Geometric Topology · Mathematics 2025-11-06 Ayaka Shimizu , Amrendra Gill , Sahil Joshi

We consider a natural model of random knotting- choose a knot diagram at random from the finite set of diagrams with n crossings. We tabulate diagrams with 10 and fewer crossings and classify the diagrams by knot type, allowing us to…

Geometric Topology · Mathematics 2016-10-12 Jason Cantarella , Harrison Chapman , Matt Mastin

A classical knot is described by a one-stroke trajectory with entanglements of a string. The replica method appears as a powerful tool in statistical mechanics for a polymer or self-avoiding walk. We consider this replica N to 0 limit in…

Mathematical Physics · Physics 2023-03-09 Shinobu Hikami

We say that a link $L_1$ is an s-major of a link $L_2$ if any diagram of $L_1$ can be transformed into a diagram of $L_2$ by changing some crossings and smoothing some crossings. This relation is a partial ordering on the set of all prime…

Geometric Topology · Mathematics 2008-06-24 Toshiki Endo , Tomoko Itoh , Kouki Taniyama

Simple closed curves in the plane can be mapped to nontrivial knots under the action of origami foldings that allow the paper to self-intersect. We show all tame knot types may be produced in this manner, motivating the development of a new…

Geometric Topology · Mathematics 2021-05-05 Joseph Slote , Thomas Bertschinger

Knotoid theory is a generalization of knot theory introduced by Turaev in 2012. In recent years, various invariants of knotoids have been studied. In this paper, we mainly discuss unknotting moves and unknotting numbers of plus-welded…

Geometric Topology · Mathematics 2026-01-28 Fengling Li , Andrei Vesnin , Xuan Yang

For a knot K, the concordance crosscap number, c(K), is the minimum crosscap number among all knots concordant to K. Building on work of G. Zhang, which studied the determinants of knots with c(K) < 2, we apply the Alexander polynomial to…

Geometric Topology · Mathematics 2013-10-29 Charles Livingston

Let $K$ be a genus $g$ alternating knot with Alexander polynomial $\Delta_K(T)=\sum_{i=-g}^ga_iT^i$. We show that if $|a_g|=|a_{g-1}|$, then $K$ is the torus knot $T_{2g+1,\pm2}$. This is a special case of the Fox Trapezoidal Conjecture.…

Geometric Topology · Mathematics 2020-07-30 Yi Ni

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 present a complete classification of spherical knotoids with up to six crossings and conjecture that our classification up to seven crossings is complete. Our work extends the tradition of knot tabulation to the setting of knotoids…

Geometric Topology · Mathematics 2026-03-09 Boštjan Gabrovšek , Paolo Cavicchioli

X.S. Lin and O. Dasbach proved that the sum of the absolute value of the second and penultimate coefficients of the Jones polynomial of an alternating knot is equal to the twist number of the knot. In this paper we give a new proof of their…

Geometric Topology · Mathematics 2007-05-23 Robert G. Todd

If a rectangular diagram represents the trivial knot, then it can be deformed into the rectangular diagram with only two vertical edges by a finite sequence of merge operations and exchange operations, without increasing the number of…

Geometric Topology · Mathematics 2013-03-28 Chuichiro Hayashi , Sayaka Yamada

We show that if $p/q$-surgery on a nontrivial knot $K$ yields the branched double cover of an alternating knot or link, then $|p/q|\leq 4g(K)+3$. This generalises a bound for lens space surgeries first established by Rasmussen. We also show…

Geometric Topology · Mathematics 2018-03-16 Duncan McCoy