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Related papers: Some remarks on the chord index

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The stick index of a knot is the least number of line segments required to build the knot in space. We define two analogous 2-dimensional invariants, the planar stick index, which is the least number of line segments in the plane to build a…

Geometric Topology · Mathematics 2011-08-30 Colin Adams , Dan Collins , Katherine Hawkins , Charmaine Sia , Rob Silversmith , Bena Tshishiku

We introduce and study so-called self-indexed graphs. These are (oriented) finite graphs endowed with a map from the set of edges to the set of vertices. Such graphs naturally arise from classical knot and link diagrams. In fact, the graphs…

Geometric Topology · Mathematics 2007-05-23 Matias Graña , Vladimir Turaev

Defined by Joyce and Matveev, the fundamental quandle is a complete invariant of oriented classical knots. We consider invariants of knots defined from quotients of the fundamental quandle. In particular, we introduce the fundamental Latin…

Geometric Topology · Mathematics 2014-04-25 Sam Nelson , Sherilyn Tamagawa

We consider the question of which virtual knots have finite fundamental medial bikei. We describe and implement an algorithm for completing a presentation matrix of a medial bikei to an operation table, determining both the cardinality and…

Geometric Topology · Mathematics 2017-04-05 Julien Chien , Sam Nelson

The multi-variable affine index polynomial was defined by the author in previous work. The aim of this short note is to update the definition so it is generalizable to virtual tangles and to show it is compatible with tangle decomposition.…

Geometric Topology · Mathematics 2022-07-26 Nicolas Petit

Given a group endowed with a Z/2-valued morphism we associate a Gauss diagram theory, and show that for a particular choice of the group these diagrams encode faithfully virtual knots on a given arbitrary surface. This theory contains all…

Geometric Topology · Mathematics 2014-03-17 Arnaud Mortier

The braid indices of most links remain unknown as there is no known universal method that can be used to determine the braid index of an arbitrary knot. This is also the case for alternating knots. In this paper, we show that if $K$ is an…

Geometric Topology · Mathematics 2024-08-28 Yuanan Diao , Hugh Morton

We introduce a new technique for studying classical knots with the methods of virtual knot theory. Let $K$ be a knot and $J$ a knot in the complement of $K$ with $\text{lk}(J,K)=0$. Suppose there is covering space $\pi_J: \Sigma \times…

Geometric Topology · Mathematics 2013-08-14 Micah W. Chrisman , Vassily O. Manturov

We introduce the warping crossing polynomial of an oriented knot diagram by using the warping degrees of crossing points of the diagram. Given a closed transversely intersected plane curve, we consider oriented knot diagrams obtained from…

Geometric Topology · Mathematics 2011-12-20 Akio Kawauchi , Ayaka Shimizu

Vassiliev invariants can be studied by studying the spaces of chord diagrams associated with singular knots. To these chord diagrams are associated the intersection graphs of the chords. We extend results of Chmutov, Duzhin and Lando to…

Geometric Topology · Mathematics 2009-09-25 Blake Mellor

We introduce two new families of polynomial invariants of oriented classical and virtual knots and links defined as decategorfications of the quandle coloring quiver. We provide examples to illustrate the computation of the invariants, show…

Geometric Topology · Mathematics 2025-08-18 Anusha Kabra , Sam Nelson

Virtual knot theory has experienced a lot of nice features that did not appear in classical knot theory, e.g., parity and picture-valued invariants. In the present paper we use virtual knot theory effects to construct new representations of…

Geometric Topology · Mathematics 2023-03-03 V. O. Manturov , I. M. Nikonov

The aim of the present paper is to construct series of invariants of free knots (flat virtual knots, virtual knots) valued in free groups (and also free products of cyclic groups). (Some minor mistakes are corrected)

Algebraic Topology · Mathematics 2021-02-23 Vassily Olegovich Manturov

Pseudodiagrams are knot or link diagrams where some of the crossing information is missing. Pseudoknots are equivalence classes of pseudodiagrams, where equivalence is generated by a natural set of Reidemeister moves. In this paper, we…

Geometric Topology · Mathematics 2013-11-15 Francois Dorais , Allison Henrich , Slavik Jablan , Inga Johnson

We introduce the warping matrix which is a new description of oriented knots from a viewpoint of warping degree.

Geometric Topology · Mathematics 2015-08-17 Ayaka Shimizu

The forbidden moves in virtual knot theory can be used to unknot any knot, virtual or classical; however, multi-component crossings in links can still survive, resulting a fused link. Using the forbidden moves, we categorify fused links…

Geometric Topology · Mathematics 2026-05-22 Sam Nelson , Stella Shah

In this paper we discuss the applications of knotoids to modelling knots in open curves and produce new knotoid invariants. We show how invariants of knotoids generally give rise to well-behaved measures of how much an open curve is…

Geometric Topology · Mathematics 2023-06-14 Wout Moltmaker , Roland van der Veen

We introduce an equivalence relation, called stable equivalence, on knot diagrams and closed curves on surfaces. We give bijections between the set of abstract knots, the set of virtual knots, and the set of the stable equivalence classes…

Geometric Topology · Mathematics 2007-05-23 J. Scott Carter , Seiichi Kamada , Masahico Saito

A virtual knot that has a homologically trivial representative $\mathscr{K}$ in a thickened surface $\Sigma \times [0,1]$ is said to be an almost classical (AC) knot. $\mathscr{K}$ then bounds a Seifert surface $F\subset \Sigma \times…

Geometric Topology · Mathematics 2017-12-18 Micah Chrisman

We define new notions of groups of virtual and welded knots (or links) and we study their relations with other invariants, in particular the Kauffman group of a virtual knot.

Geometric Topology · Mathematics 2012-04-17 Valeriy G. Bardakov , Paolo Bellingeri