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Related papers: On Virtual Crossing Numbers for Virtual Knots

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In this paper we give the results of a computer search for biracks of small size and we give various interpretations of these findings. The list includes biquandles, racks and quandles together with new invariants of welded knots and…

Geometric Topology · Mathematics 2010-04-09 Andrew Bartholomew , Roger Fenn

There are 46,972 prime knots with crossing number 14. Among them 19,536 are alternating and have arc index 16. Among the non-alternating knots, 17, 477, and 3,180 have arc index 10, 11, and 12, respectively. The remaining 23,762 have arc…

For classical links Ohyama proved an inequality involving the minimal crossing number and the braid index, then motivated from this Takeda showed an analogous inequality for virtual links. In this paper, we are interested in studying…

Geometric Topology · Mathematics 2025-11-05 Gustavo Cardoso , Oscar Ocampo

In the present paper, we consider local moves on classical and welded diagrams: (self-)crossing change, (self-)virtualization, virtual conjugation, Delta, fused, band-pass and welded band-pass moves. Interrelationship between these moves is…

Geometric Topology · Mathematics 2019-10-25 Benjamin Audoux , Paolo Bellingeri , Jean-Baptiste Meilhan , Emmanuel Wagner

We use matchings on Lyndon words to classify flat knots up to 8 crossings. Using flat knots invariants such as the based matrix, the $\phi$-invariant, the flat arrow polynomial, and the flat Jones-Krushkal polynomial, we distinguish all…

Geometric Topology · Mathematics 2024-10-02 Jie Chen

The stick number of a knot is the minimum number of segments needed to build a polygonal version of the knot. Despite its elementary definition and relevance to physical knots, the stick number is poorly understood: for most knots we only…

Geometric Topology · Mathematics 2023-01-09 Thomas D. Eddy , Clayton Shonkwiler

We show that a knot whose minimum crossing number $c(K)$ is even and greater than $30$ is not fertile; there exists a knot $K'$ with crossing number less than $c$ such that $K'$ is not obtained from a minimum crossing number diagram of $K$…

Geometric Topology · Mathematics 2021-11-30 Tetsuya Ito

Traditionally, knot theorists have considered projections of knots where there are two strands meeting at every crossing. A multi-crossing is a crossing where more than two strands meet at a single point, such that each strand bisects the…

Geometric Topology · Mathematics 2018-05-14 Daishiro Nishida

We establish a new fundamental relationship between total curvature of knots and crossing number. If K is a smooth knot in 3-space, R the cross-section radius of a uniform tube neighborhood of K, L the arclength of K, and k the total…

Geometric Topology · Mathematics 2007-05-23 Gregory Buck , Jonathan Simon

Given a diagram $D$ of a knot $K$, we consider the number $c(D)$ of crossings and the number $b(D)$ of overpasses of $D$. We show that, if $D$ is a diagram of a nontrivial knot $K$ whose number $c(D)$ of crossings is minimal, then…

Geometric Topology · Mathematics 2009-11-10 Jae-Wook Chung , Xiao-Song Lin

In this paper, we discuss filamentations on oriented chord diagrams. When a filamentation cannot be realized on an oriented chord diagram, then the corresponding flat virtual knot is non-trivial. If a flat knot diagram is non-trivial, then…

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

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

We introduce an unknotting-type number of knot projections that gives an upper bound of the crosscap number of knots. We determine the set of knot projections with the unknotting-type number at most two, and this result implies classical…

Geometric Topology · Mathematics 2020-08-26 Noboru Ito , Yusuke Takimura

Virtual links are generalizations of classical links that can be represented by links embedded in a ``thickened'' surface $\Sigma\times I$, product of a Riemann surface of genus $h$ with an interval. In this paper, we show that virtual…

Mathematical Physics · Physics 2007-05-23 P. Zinn-Justin , J. -B. Zuber

The crossing number of a graph is the minimum number of edge crossings that a graph can have when drawn in the plane. Determining this number, known as the Crossing Number problem, is a celebrated problem in combinatorial optimization. It…

Computational Geometry · Computer Science 2026-03-30 Petr Hliněný , Liana Khazaliya

The splitting number of a link is the minimum number of crossing changes between distinct components that is required to convert the link into a split link. We provide a bound on the splitting number in terms of the four-genus of related…

Geometric Topology · Mathematics 2018-06-13 Charles Livingston

Ropelength and embedding thickness are related measures of geometric complexity of classical knots and links in Euclidean space. In their recent work, Freedman and Krushkal posed a question regarding lower bounds for embedding thickness of…

Geometric Topology · Mathematics 2020-01-14 R. Komendarczyk , A. Michaelides

The genus non-increasing totally positive unknotting number is the minimum number of crossing changes that transform a knot into the unknot, such that all the crossing changes are positive-to-negative crossing changes that do not increase…

Geometric Topology · Mathematics 2024-06-24 Tetsuya Ito

We introduce an infinite family of quantum enhancements of the biquandle counting invariant we call biquandle virtual brackets. Defined in terms of skein invariants of biquandle colored oriented knot and link diagrams with values in a…

Geometric Topology · Mathematics 2019-08-28 Sam Nelson , Kanako Oshiro , Ayaka Shimizu , Yoshiro Yaguchi

We define an invariant of welded virtual knots from each finite crossed module by considering crossed module invariants of ribbon knotted surfaces which are naturally associated with them. We elucidate that the invariants obtained are non…

Geometric Topology · Mathematics 2017-05-23 Louis H. Kauffman , João Faria Martins