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Minimum braids are a complete invariant of knots and links. This paper defines minimum braids, describes how they can be generated, presents tables for knots up to ten crossings and oriented links up to nine crossings, and uses minimum…

Geometric Topology · Mathematics 2007-05-23 Thomas A. Gittings

We take a close look at a classical magic trick performed with a string, where a trivial knot is seemingly isotoped into a trefoil, and generalize it to a family of magic tricks for transforming the unknot into other knots. We encode such a…

Geometric Topology · Mathematics 2026-04-16 Raphael Appenzeller , José Pedro Quintanilha

We present computational results about quasi-alternating knots and links and odd homology obtained by looking at link families in the Conway notation. More precisely, we list quasi-alternating links up to 12 crossings and the first examples…

Geometric Topology · Mathematics 2014-04-01 Slavik Jablan , Radmila Sazdanović

There is a positive constant $c_1$ such that for any diagram $D$ representing the unknot, there is a sequence of at most $2^{c_1 n}$ Reidemeister moves that will convert it to a trivial knot diagram, $n$ is the number of crossings in $D$. A…

Geometric Topology · Mathematics 2007-05-23 Joel Hass , Jeffrey C. Lagarias

Let $K$ be a link of Conway's normal form $C(m)$, $m \geq 0$, or $C(m,n)$ with $mn\textgreater{}0$, and let $D$ be a trigonal diagram of $K.$ We show that it is possible to transform $D$ into an alternating trigonal diagram, so that all…

Geometric Topology · Mathematics 2014-11-25 Erwan Brugallé , Pierre-Vincent Koseleff , Daniel Pecker

Graph pebbling considers the problem of transforming configurations of discrete pebbles to certain target configurations on the vertices of a graph, using the so-called pebbling move. This paper provides counterexamples to a monotonicity…

Combinatorics · Mathematics 2011-07-26 Johan Björklund , Cecilia Holmgren

Conjecture $\mathbb{Z}$ is a knot theoretical equivalent form of the Kervaire Conjecture. We say that a knot have property $\mathbb{Z}$ if it satisfies Conjecture $\mathbb{Z}$ for that specific knot. In this work, we show that alternating…

Geometric Topology · Mathematics 2016-09-28 Jesús Rodríguez-Viorato

Given a knot diagram $D$, we construct a semi-threading circle for it which can be an axis of $D$ as a closed braid depending on knot diagrams. In particular, we consider semi-threading circles for minimal diagrams of a knot with respect to…

General Topology · Mathematics 2013-02-18 Jae-Wook Chung , Seulgi Jeong , Dongseok Kim

In this paper, we study knot diagrams for which the underlying graph has treewidth two. We give a linear time algorithm for the following problem: given a knot diagram of treewidth two, does it represent the unknot? We also show that for a…

Data Structures and Algorithms · Computer Science 2019-04-09 Hans L. Bodlaender , Benjamin Burton , Fedor V. Fomin , Alexander Grigoriev

In this paper we introduce a new invariant of virtual knots and links that is non-trivial for infinitely many virtuals, but is trivial on classical knots and links. The invariant is initially be expressed in terms of a relative of the…

Geometric Topology · Mathematics 2007-05-23 Louis H. Kauffman

A link is almost alternating if it is non-alternating and has a diagram that can be transformed into an alternating diagram via one crossing change. We give formulas for the first two and last two potential coefficients of the Jones…

Geometric Topology · Mathematics 2017-12-18 Adam M. Lowrance , Dean Spyropoulos

The AJ Conjecture relates a quantum invariant, a minimal order recursion for the colored Jones polynomial of a knot (known as the $\hat{A}$ polynomial), with a classical invariant, namely the defining polynomial $A$ of the $\psl$ character…

Geometric Topology · Mathematics 2019-03-06 Renaud Detcherry , Stavros Garoufalidis

It is known that the unknotting number $u(L)$ of a link $L$ is less than or equal to half the crossing number $c(L)$ of $L$. We show that there are a planar graph $G$ and its spatial embedding $f$ such that the unknotting number $u(f)$ of…

Geometric Topology · Mathematics 2020-10-13 Yuta Akimoto , Kouki Taniyama

We showed that the order of torsion homology classes in the grid homology of a knot is a lower bound for the unknotting number.

Geometric Topology · Mathematics 2022-03-01 Zipei Zhuang

The n-th crossing number of a graph G, denoted cr_n(G), is the minimum number of crossings in a drawing of G on an orientable surface of genus n. We prove that for every a>b>0, there exists a graph G for which cr_0(G) = a, cr_1(G) = b, and…

Combinatorics · Mathematics 2010-09-06 Matt DeVos , Bojan Mohar , Robert Samal

For an oriented link diagram D, the warping degree d(D) is the smallest number of crossing changes which are needed to obtain a monotone diagram from D. We show that d(D)+d(-D)+sr(D) is less than or equal to the crossing number of D, where…

Geometric Topology · Mathematics 2009-12-27 Ayaka Shimizu

We study knots in $\mathbb{S}^3$ obtained by the intersection of a minimal surface in $\mathbb{R}^4$ with a small 3-sphere centered at a branch point. We construct examples of new minimal knots. In particular we show the existence of…

Differential Geometry · Mathematics 2007-05-23 Marc Soret , Marina Ville

Any knot diagram can be transformed into the unknot by a series of unknotting operations. This paper introduces the diagonal move, a novel unknotting operation that generalizes and unifies several existing moves. We prove that the diagonal…

Geometric Topology · Mathematics 2026-03-19 Danish Ali , Zhiqing Yang , Mohd Ibrahim Sheikh , Sidra Batool

We define the concordance crosscap number of a knot as the minimum crosscap number among all the knots concordant to the knot. The four-dimensional crosscap number is the minimum first Betti number of non-orientable surfaces smoothly…

Geometric Topology · Mathematics 2007-05-23 Gengyu Zhang

Neuwirth asked if any non-trivial knot in the 3-sphere can be embedded in a closed surface so that the complement of the surface is a connected essential surface for the knot complement. In this paper, we examine some variations on this…

Geometric Topology · Mathematics 2011-03-15 Makoto Ozawa , J. Hyam Rubinstein