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Related papers: The unknotting numbers for plus-welded knotoids

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We show that a topological quantum computer based on the evaluation of a Witten-Reshetikhin-Turaev TQFT invariant of knots can always be arranged so that the knot diagrams with which one computes are diagrams of hyperbolic knots. The…

Quantum Physics · Physics 2023-05-08 Eric Samperton

Region crossing change for a knot or a proper link is an unknotting operation. In this paper, we provide a sharp upper bound on the region unknotting number for a large class of torus knots and proper links. Also, we discuss conditions on…

Geometric Topology · Mathematics 2013-05-30 Vikash Siwach , Madeti Prabhakar

A theorem of Kronheimer and Mrowka states that Khovanov homology is able to detect the unknot. That is, if a knot has the Khovanov homology of the unknot, then it is equivalent to it. Similar results hold for the trefoils and the…

Geometric Topology · Mathematics 2026-04-07 Vladimir Chernov , Ryan Maguire

According to the idea of Ozsv\'ath, Stipsicz and Szab\'o, we define the knot invariant $\Upsilon$ without the holomorphic theory, using constructions from grid homology. We develop a homology theory using grid diagrams, and show that…

Geometric Topology · Mathematics 2019-03-15 Viktória Földvári

For $p\geq 1$ one can define a generalization of the unknotting number $tu_p$ called the $p$th untwisting number which counts the number of null-homologous twists on at most $2p$ strands required to convert the knot to the unknot. We show…

Geometric Topology · Mathematics 2020-12-16 Duncan McCoy

A polynomial is presented that models a topological knot in a unique manner. It distinguishes all types of knots including the orientation and has a group theory interpretation. The topologies may be labeled via a number, which upon a base…

General Physics · Physics 2007-05-23 Gordon Chalmers

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

We construct families of trivial $2$-knots $K_i$ in $\mathbb{R}^4$ such that the maximal complexity of $2$-knots in any isotopy connecting $K_i$ with the standard unknot grows faster than a tower of exponentials of any fixed height of the…

Metric Geometry · Mathematics 2019-12-17 Boris Lishak , Alexander Nabutovsky

In this paper we study welded knots and their invariants. We focus on generating examples of non-trivial knotted ribbon tori as the tube of welded knots that are obtained from classical knot diagrams by welding some of the crossings.…

Geometric Topology · Mathematics 2024-04-02 Tumpa Mahato , Rama Mishra , Sahil Joshi

A new type of knot energy is presented via real life experiments involving a thin resilient metallic tube. Knotted in different ways, the device mechanically acquires a uniquely determined (up to isometry) normal form at least when the…

Geometric Topology · Mathematics 2015-05-20 A. B. Sossinsky

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

In this paper we discuss the applications of knotoids to modelling knots in open curves and produce new knotoid invariants. We show how invariants of knotoids generally give rise to well-behaved measures of how much an open curve is…

Geometric Topology · Mathematics 2023-06-14 Wout Moltmaker , Roland van der Veen

We introduce a new combinatorial method to encode knots and links with applications to knot invariants. Clasp diagrams defined in this paper are combinatorial blueprints for building knot diagrams out of full twists on two strings rather…

Geometric Topology · Mathematics 2019-11-11 Jacob Mostovoy , Michael Polyak

In this paper, we generalize the \textit{Clock Theorem} of Formal Knot Theory to knotoids in $S^2$. The clock theorem implies that clock states of a knotoid diagram form a lattice under transpositions. These states form the basis of many…

Geometric Topology · Mathematics 2025-09-29 Neslihan Gügümcü , Louis H. Kauffman

Knotted and tangled structures frequently appear in physical fields, but so do mechanisms for untying them. To understand how this untying works, we simulate the behavior of 1,458 superfluid vortex knots of varying complexity and scale in…

Fluid Dynamics · Physics 2016-07-20 Dustin Kleckner , Louis H. Kauffman , William T. M. Irvine

We consider surface links in the 4-space which are presented by the form of simple branched coverings over the standard torus, which we call torus-covering links. In this paper, we study unknotting numbers of torus-covering links. In some…

Geometric Topology · Mathematics 2012-06-07 Inasa Nakamura

Manturov recently introduced the idea of a free knot, i.e. an equivalence class of virtual knots where equivalence is generated by crossing change and virtualization moves. He showed that if a free knot diagram is associated to a graph that…

Combinatorics · Mathematics 2014-09-18 Tomas Boothby , Allison Henrich , Alexander Leaf

This paper extends the study of arc crossing change, a local operation on knot diagrams recently introduced by Cericola, from knot diagrams to link diagrams. We consider two types of arc crossing change on link diagrams and discuss when…

Geometric Topology · Mathematics 2025-09-11 Zhiyun Cheng , Qian Liao , Jingze Song

This paper defines a new invariant of virtual knots and links that we call the extended bracket polynomial, and denote by <<K>> for a virtual knot or link K. This invariant is a state summation over bracket states of the oriented diagram…

Geometric Topology · Mathematics 2009-04-23 Louis H. Kauffman

Classical knots in $\mathbb{R}^3$ can be represented by diagrams in the plane. These diagrams are formed by curves with a finite number of transverse crossings, where each crossing is decorated to indicate which strand of the knot passes…

Geometric Topology · Mathematics 2013-09-30 Allison Henrich , Rebecca Hoberg , Slavik Jablan , Lee Johnson , Elizabeth Minten , Ljiljana Radovic