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Related papers: Virtual knots and links with unknotting index (n,m…

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We consider a natural model of random knotting- choose a knot diagram at random from the finite set of diagrams with n crossings. We tabulate diagrams with 10 and fewer crossings and classify the diagrams by knot type, allowing us to…

Geometric Topology · Mathematics 2016-10-12 Jason Cantarella , Harrison Chapman , Matt Mastin

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 study the chord index of virtual knots, which can be thought of as an extension of the chord parity. We show how to use the chord index to define finite type invariants of virtual knots. The notions of indexed Jones…

Geometric Topology · Mathematics 2026-05-26 Zhiyun Cheng

Frequently, knots are enumerated by their crossing number. However, the number of knots with crossing number $c$ grows exponentially with $c$, and to date computer-assisted proofs can only classify diagrams up to around twenty crossings.…

Geometric Topology · Mathematics 2018-12-03 Yoav Moriah , Jessica S. Purcell

Noting that cycle diagrams of permutations visually resemble grid diagrams used to depict knots and links in topology, we consider the knot (or link) obtained from the cycle diagram of a permutation. We show that the permutations which…

Combinatorics · Mathematics 2020-07-10 Christopher R. Cornwell , Nathan McNew

Let $\mathcal {M}$ be the space of all, including singular, long knots in 3-space and for which a fixed projection into the plane is an immersion. Let $cl(\Sigma^{(1)}_{iness})$ be the closure of the union of all singular knots in $\mathcal…

Geometric Topology · Mathematics 2009-03-10 Thomas Fiedler

Two natural generalizations of knot theory are the study of spatially embedded graphs, and Kauffman's theory of virtual knots. In this paper we combine these approaches to begin the study of virtual spatial graphs.

Geometric Topology · Mathematics 2009-01-10 Thomas Fleming , Blake Mellor

This paper employs various computational techniques to determine the bridge numbers of both classical and virtual knots. For classical knots, there is no ambiguity of what the bridge number means. For virtual knots, there are multiple…

Geometric Topology · Mathematics 2024-05-10 Hanh Vo , Puttipong Pongtanapaisan , Thieu Nguyen

We prove that if an alternating knot has unknotting number one, then there exists an unknotting crossing in any alternating diagram. This is done by showing that the obstruction to unknotting number one developed by Greene in his work on…

Geometric Topology · Mathematics 2017-04-11 Duncan McCoy

In the present paper we give a new method for converting virtual knots and links to virtual braids. Indeed the braiding method given in this paper is quite general, and applies to all the categories in which braiding can be accomplished. We…

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

Knot mosaic theory was introduced by Lomonaco and Kauffman in the paper on `Quantum knots and mosaics' to give a precise and workable definition of quantum knots, intended to represent an actual physical quantum system. A knot (m,n)-mosaic…

Geometric Topology · Mathematics 2017-03-16 Seungsang Oh , Kyungpyo Hong , Ho Lee , Hwa Jeong Lee , Mi Jeong Yeon

It is well-known that a knot in a contact manifold $(M,C)$ transverse to a trivialized contact structure possesses the natural framing given by the first of the trivialization vectors along the knot. If the Euler class $e_C\in H^2(M)$ of…

Symplectic Geometry · Mathematics 2007-05-23 Vladimir Chernov

Introducing a way to modify knots using $n$-trivial rational tangles, we show that knots with given values of Vassiliev invariants of bounded degree can have arbitrary unknotting number (extending a recent result of Ohyama, Taniyama and…

Geometric Topology · Mathematics 2007-05-23 A. Stoimenow

It has been an open question whether the deletion or contraction of an edge in an intrinsically knotted graph always yields an intrinsically linked graph. We present a new intrinsically knotted graph that shows the answer to both questions…

Geometric Topology · Mathematics 2024-04-24 Thomas W. Mattman , Ramin Naimi , Andrei Pavelescu , Elena Pavelescu

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, we introduce invariants of virtual knotoids based on biquandles and biquandle virtual brackets. We show that one of these invariants, namely biquandle virtual bracket matrix, is a proper enhancement of the other invariants…

Algebraic Topology · Mathematics 2025-07-11 Neslihan Gügümcü , Hamdi Kayaslan

We show that the forbidden detour move, essentially introduced by Kanenobu and Nelson, is an unknotting operation for virtual knots. Then we define the forbidden detour number of a virtual knot to be the minimal number of forbidden detour…

Geometric Topology · Mathematics 2019-08-30 Shun Yoshiike , Kazuhiro Ichihara

We construct an infinite collection of knots with the property that any knot in this family has $n$-string essential tangle decompositions for arbitrarily high $n$.

Geometric Topology · Mathematics 2017-05-19 João Miguel Nogueira

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

We derive an asymptotic formula for the number of strongly connected digraphs with $n$ vertices and $m$ arcs (directed edges), valid for $m-n\to\infty$ as $n\to \infty$ provided $m=O(n\log n)$. This fills the gap between Wright's results…

Combinatorics · Mathematics 2011-05-18 Xavier Perez-Gimenez , Nicholas Wormald