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Related papers: An unknotting index for virtual knots

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Virtual knot theory is a generalization (discovered by the author in 1996) of knot theory to the study of all oriented Gauss codes. (Classical knot theory is a study of planar Gauss codes.) Graph theory studies non-planar graphs via…

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

We define invariants of unoriented knots and links by enhancing the integral kei counting invariant Phi_X^Z (K) for a finite kei X using representations of the kei algebra, Z_K[X], a quotient of the quandle algebra Z[X] defined by…

Geometric Topology · Mathematics 2011-02-23 Mike Grier , Sam Nelson

For ordinary knots in R3, there are no degree one Vassiliev invariants. For virtual knots, however, the space of degree one Vassiliev invariants is infinite dimensional. We introduce a sequence of three degree one Vassiliev invariants of…

Geometric Topology · Mathematics 2011-09-20 Allison Henrich

We define a family of virtual knots generalizing the classical twist knots. We develop a recursive formula for the Alexander polynomial $\Delta_0$ (as defined by Silver and Williams) of these virtual twist knots. These results are applied…

Geometric Topology · Mathematics 2018-08-14 Isaac Benioff , Blake Mellor

This paper is an introduction to the theory of virtual knots and links and it gives a list of unsolved problems in this subject.

Geometric Topology · Mathematics 2007-05-23 Roger Fenn , Louis H. Kauffman , Vassily O. Manturov

In this paper we construct new invariants of knotoids including the odd writhe, the parity bracket polynomial, the affine index polynomial and the arrow polynomial, and give an introduction to the theory of virtual knotoids. The invariants…

Geometric Topology · Mathematics 2018-01-30 Neslihan Gügümcü , Louis H. Kauffman

We study virtualized Delta, sharp, and pass moves for oriented virtual links, and give necessary and sufficient conditions for two oriented virtual links to be related by the local moves. In particular, they are unknotting operations for…

Geometric Topology · Mathematics 2024-01-25 Takuji Nakamura , Yasutaka Nakanishi , Shin Satoh , Kodai Wada

The unknotting number of a positive braid with n strands and k intersections is known to be equal to (k-n+1)/2. We consider Lorenz knots (which are positive braids) and, using a different method, find their unknotting numbers in terms of…

Geometric Topology · Mathematics 2015-03-04 Lilya Lyubich

It is an open question whether there are Vassiliev invariants that can distinguish an oriented knot from its inverse, i.e., the knot with the opposite orientation. In this article, an example is given for a first order Vassiliev invariant…

Geometric Topology · Mathematics 2007-05-23 J. Sawollek

There are three commonly known definitions of the bridge index. These definitions come from combinatorial knot theory, Morse theory, and geometry. In this paper, we prove that the danceability index is a fourth equivalent definition of the…

Geometric Topology · Mathematics 2024-12-23 Sol Addison , Nancy Scherich , Lila Snodgrass , Everett Sullivan

In this paper, the authors give an unknotting sequence for torus knots and also provide unknotting numbers of $_n14_{17191}, \ _n14_{14274}, \ _n14_{18351}, \ _n14_{24498}$ and some other knots from the knot table of Hoste-Thistlethwite.

Geometric Topology · Mathematics 2014-02-04 Vikash Siwach , Madeti Prabhakar

In this paper, we define the parity virtual Alexander polynomial following the work of BDGGHN [1] and Kaestner and Kauffman [10]. The properties of this invariant are explored and some examples are computed. In particular, the invariant…

Geometric Topology · Mathematics 2019-07-23 Heather A. Dye , Aaron Kaestner

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

We define a multi-variable version of the Affine Index Polynomial for virtual links. This invariant reduces to the original Affine Index Polynomial in the case of virtual knots, and also generalizes the version for compatible virtual links…

Geometric Topology · Mathematics 2019-09-11 Nicolas Petit

We define counting and cocycle enhancement invariants of virtual knots using parity biquandles. These invariants are determined by pairs consisting of a biquandle 2-cocycle \phi^0 and a map \phi^1 with certain compatibility conditions…

Geometric Topology · Mathematics 2016-06-16 Aaron Kaestner , Sam Nelson , Leo Selker

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

We compute many dimensions of spaces of finite type invariants of virtual knots (of several kinds) and the dimensions of the corresponding spaces of "weight systems", finding everything to be in agreement with the conjecture that "every…

Geometric Topology · Mathematics 2009-09-29 Dror Bar-Natan , Iva Halacheva , Louis Leung , Fionntan Roukema

We introduce twelve polynomial invariants for long virtual knots, called intersection polynomials, extending and refining the three intersection polynomials for virtual knots. They are defined via intersection numbers of cycles on a closed…

Geometric Topology · Mathematics 2025-12-08 Takuji Nakamura , Yasutaka Nakanishi , Shin Satoh , Kodai Wada

A virtual knot, which is one of generalizations of knots in $\mathbb{R}^{3}$ (or $S^{3}$), is, roughly speaking, an embedded circle in thickened surface $S_{g} \times I$. In this talk we will discuss about knots in 3 dimensional $S_{g}…

Geometric Topology · Mathematics 2022-01-03 Seongjeong Kim

In this paper, we formulate a new local move on virtual knot diagram, called arc shift move. Further, we extend it to another local move called region arc shift defined on a region of a virtual knot diagram. We establish that these arc…

Geometric Topology · Mathematics 2018-08-14 K. Kaur , A. Gill , M. Prabhakar