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Related papers: PL-virtual knots

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A virtual knot is an equivalence class of embeddings of $ S^1 $ into thickened (closed oriented) surfaces, up to self-diffeomorphism of the surface and certain handle stabilisations. The slice genus of a virtual knot is defined…

Geometric Topology · Mathematics 2018-12-14 William Rushworth

Computational topology is a vibrant contemporary subfield and this article integrates knot theory and mathematical visualization. Previous work on computer graphics developed a sequence of smooth knots that were shown to converge point wise…

Geometric Topology · Mathematics 2016-03-29 J. Li , T. J. Peters , K. E. Jordan , P. Zaffetti

We introduce a local deformation called the virtualized $\Delta$-move for virtual knots and links. We prove that the virtualized $\Delta$-move is an unknotting operation for virtual knots. Furthermore we give a necessary and sufficient…

Geometric Topology · Mathematics 2024-01-24 Takuji Nakamura , Yasutaka Nakanishi , Shin Satoh , Kodai Wada

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 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 primary objects of study in the ``knot theory of complex plane curves'' are C-links: links (or knots) cut out of a 3-sphere in the complex plane by complex plane transverse and totally tangential. Transverse C-links are naturally…

Geometric Topology · Mathematics 2007-05-23 Lee Rudolph

We define a group-valued invariant of virtual knots and relate it to various other group-valued invariants of virtual knots, including the extended group of Silver-Williams and the quandle group of Manturov and Bardakov-Bellingeri. A…

Geometric Topology · Mathematics 2017-07-14 Hans U. Boden , Robin Gaudreau , Eric Harper , Andrew J. Nicas , Lindsay White

The writhe polynomial is a fundamental invariant of an oriented virtual knot. We introduce a kind of local moves for oriented virtual knots called shell moves. The first aim of this paper is to prove that two oriented virtual knots have the…

Geometric Topology · Mathematics 2019-05-10 Takuji Nakamura , Yasutaka Nakanishi , Shin Satoh

We introduce a notion of intrinsic linking and knotting for virtual spatial graphs. Our theory gives two filtrations of the set of all graphs, allowing us to measure, in a sense, how intrinsically linked or knotted a graph is; we show that…

Geometric Topology · Mathematics 2014-10-01 Thomas Fleming , Blake Mellor

We consider several classes of knotted objects, namely usual, virtual and welded pure braids and string links, and two equivalence relations on those objects, induced by either self-crossing changes or self-virtualizations. We provide a…

Geometric Topology · Mathematics 2017-11-30 Benjamin Audoux , Paolo Bellingeri , Jean-Baptiste Meilhan , Emmanuel Wagner

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

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 paper we will discuss about knots in 3 dimensional $S_{g}…

Geometric Topology · Mathematics 2022-01-03 Seongjeong Kim

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

The notion of a virtual knot introduced by L. Kauffman induces the notion of a virtual braid. It is closely related with a welded braid of R. Fenn, R. Rimanyi and C. Rourke. Alexander's and Markov's theorems for virtual knots and braids are…

Geometric Topology · Mathematics 2007-05-23 Seiichi Kamada

The connected sum of two flat virtual knots depends on the choice of diagrams and basepoints. We show that any minimal crossing diagram of a composite flat virtual knot is a connected sum diagram. We also show the crossing number of flat…

Geometric Topology · Mathematics 2024-07-26 Jie Chen

In 2002, D. Hrencecin and L.H. Kauffman defined a filamentation invariant on oriented chord diagrams that may determine whether the corresponding flat virtual knot diagrams are non-trivial. A virtual knot diagram is non-classical if its…

Geometric Topology · Mathematics 2007-05-23 William J. Schellhorn

In this paper, we define some polynomial invariants for virtual knots and links. In the first part we use Manturov's parity axioms to obtain a new polynomial invariant of virtual knots. This invariant can be regarded as a generalization of…

Geometric Topology · Mathematics 2013-12-31 Zhiyun Cheng , Hongzhu Gao

For a virtual knot $K$ and an integer $r\geq 0$, the $r$-covering $K^{(r)}$ is defined by using the indices of chords on a Gauss diagram of $K$. In this paper, we prove that for any finite set of virtual knots $J_0,J_2,J_3,\dots,J_m$, there…

Geometric Topology · Mathematics 2018-11-28 Takuji Nakamura , Yasutaka Nakanishi , Shin Satoh

We classify positive transversal torus knots in tight contact structures up to transversal isotopy.

Geometric Topology · Mathematics 2014-11-11 John B. Etnyre

We introduce an algebraic structure we call semiquandles whose axioms are derived from flat Reidemeister moves. Finite semiquandles have associated counting invariants and enhanced invariants defined for flat virtual knots and links. We…

Geometric Topology · Mathematics 2011-09-20 Allison Henrich , Sam Nelson