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Related papers: Knot invariants for rail knotoids

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As a generalization of the classical knots, knotoids deal with the open ended knot diagrams in a surface. In recent years, many polynomial invariants for knotoids have appeared, such as the bracket polynomial, the index polynomial and the…

Geometric Topology · Mathematics 2023-12-27 Yi Feng , Fengling Li

In this paper we describe what should perhaps be called a `type-2' Vassiliev invariant of knots S^2 -> S^4. We give a formula for an invariant of 2-knots, taking values in Z_2 that can be computed in terms of the double-point diagram of the…

Geometric Topology · Mathematics 2026-01-13 Ryan Budney

A {\it stuck knot} is a knot diagram containing designated crossings, called {\it stuck crossings}, whose incident strands are required to remain locally non-separable. These rigidity constraints restrict the allowable ambient isotopies and…

Geometric Topology · Mathematics 2026-02-23 Ioannis Diamantis

Virtual knot theory is a generalization of knot theory which is based on Gauss chord diagrams and link diagrams on closed oriented surfaces. A twisted knot is a generalization of a virtual knot, which corresponds to a link diagram on a…

Geometric Topology · Mathematics 2015-12-04 Naoko Kamada

Given any oriented link diagram, two types of new knot invariants are constructed. They satisfy some generalized skein relations. The coefficients of each invariant is from a commutative ring. Homomorphisms and representations of those…

Geometric Topology · Mathematics 2011-05-10 Zhiqing Yang

We show that Rasmussen's invariant of knots, which is derived from Lee's variant of Khovanov homology, is equal to an analogous invariant derived from certain other filtered link homologies.

Geometric Topology · Mathematics 2012-07-06 Marco Mackaay , Paul Turner , Pedro Vaz

This paper contains the first knot polynomials which can distinguish the orientations of classical knots and which make no excplicit use of the knot group. But they make extensive use of the meridian and of the longitude in a geometric way.…

Geometric Topology · Mathematics 2023-01-18 Thomas Fiedler

We exhibit pairs of transverse knots with the same self-linking number that are not transversely isotopic, using the recently defined knot Floer homology invariant for transverse knots and some algebraic refinements of it.

Geometric Topology · Mathematics 2010-03-15 Lenhard Ng , Peter Ozsvath , Dylan Thurston

In this article, we prove the conjecture of Bar-Natan, Garoufalidis, and Khovanov's on the support of the Khovanov's invariants for alternating knots.

Geometric Topology · Mathematics 2007-05-23 Eun Soo Lee

We consider an analogue of well-known Casson knot invariant for knotoids. We start with a direct analogue of the classical construction which gives two different integer-valued knotoid invariants and then focus on its homology extension.…

Geometric Topology · Mathematics 2020-09-29 Vladimir Tarkaev

In this paper, we construct invariants of braids, knots and links by studying dynamics of points in $\R^{2}$ and applying the Ptolemy relation $ac+bd=xy$.

Geometric Topology · Mathematics 2019-01-23 Vassily Olegovich Manturov

This paper deals with the study of a new family of knot invariants: the $L^2$-Alexander invariant. A main result is to give a method of computation of the $L^2$-Alexander invariant of a knot complement using any presentation of default 1 of…

Geometric Topology · Mathematics 2013-03-27 Jérôme Dubois , Christian Wegner

We introduce and study knotoids. Knotoids are represented by diagrams in a surface which differ from the usual knot diagrams in that the underlying curve is a segment rather than a circle. Knotoid diagrams are considered up to Reidemeister…

Geometric Topology · Mathematics 2011-04-14 Vladimir Turaev

Twisted Alexander invariants of knots are well-defined up to multiplication of units. We get rid of this multiplicative ambiguity via a combinatorial method and define normalized twisted Alexander invariants. We then show that the…

Geometric Topology · Mathematics 2015-07-07 Takahiro Kitayama

Concordance invariants of knots are derived from the instanton homology groups with local coefficients, as introduced in earlier work of the authors. These concordance invariants include a 1-parameter family of homomorphisms $f_{r}$, from…

Geometric Topology · Mathematics 2021-02-03 Peter B. Kronheimer , Tomasz S. Mrowka

We define ambient isotopy invariants of oriented knots and links using the counting invariants of framed links defined by finite racks. These invariants reduce to the usual quandle counting invariant when the rack in question is a quandle.…

Geometric Topology · Mathematics 2013-07-30 Sam Nelson

Given any unoriented link diagram, a group of new knot invariants are constructed. Each of them satisfies a generalized 4 term skein relation. The coefficients of each invariant is from a commutative ring. Homomorphisms and representations…

Geometric Topology · Mathematics 2010-04-14 Zhiqing Yang , Jifu Xiao

We present a topological interpretation of knot and braid contact homology in degree zero, in terms of cords and skein relations. This interpretation allows us to extend the knot invariant to embedded graphs and higher-dimensional knots. We…

Geometric Topology · Mathematics 2014-11-11 Lenhard Ng

We make use of the 3D nature of knots and links to find savings in computational complexity when computing knot invariants such as the linking number and, in general, most finite type invariants. These savings are achieved in comparison…

Geometric Topology · Mathematics 2024-01-15 Dror Bar-Natan , Itai Bar-Natan , Iva Halacheva , Nancy Scherich

We present two different constructions of invariants for Legendrian knots in the standard contact space $\R^3$. These invariants are defined combinatorially, in terms of certain planar projections, and are useful in distinguishing…

Geometric Topology · Mathematics 2007-05-23 Yuri Chekanov