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Related papers: Unknotting number for Lorenz knots

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We study Kauffman's model of folded ribbon knots: knots made of a thin strip of paper folded flat in the plane. The folded ribbonlength is the length to width ratio of such a folded ribbon knot. The folded ribbon knot is also a framed knot,…

Geometric Topology · Mathematics 2025-09-24 Elizabeth Denne , Troy Larsen

We present experimental results on knotting in off-lattice self-avoiding polygons in the bead-chain model. Using Clisby's tree data structure and the scale-free pivot algorithm, for each $k$ between $10$ and $27$ we generated $2^{43-k}$…

Statistical Mechanics · Physics 2026-05-19 Jason Cantarella , Tetsuo Deguchi , Henrik Schumacher , Clayton Shonkwiler , Erica Uehara

The slicing number of a knot, $u_s(K)$, is the minimum number of crossing changes required to convert $K$ to a slice knot. This invariant is bounded above by the unknotting number and below by the slice genus $g_s(K)$. We show that for many…

Geometric Topology · Mathematics 2008-02-18 Brendan Owens

We study positive braid knots (the knots in the three-sphere realized as positive braid closures) through the lens of the L-space conjecture. This conjecture predicts that if $K$ is a non-trivial positive braid knot, then for all $r <…

Geometric Topology · Mathematics 2025-04-07 Siddhi Krishna

We showed that the order of torsion homology classes in the grid homology of a knot is a lower bound for the unknotting number.

Geometric Topology · Mathematics 2022-03-01 Zipei Zhuang

Generalizing unknotting number, $n$-adjacent knots have $n$ crossings such that changing any non-empty subset of them results in the unknot. In this paper, we determine the 2-adjacent knots through 12 crossings. Using Heegaard Floer…

Geometric Topology · Mathematics 2025-10-02 John Carney , Everett Meike

In this paper we introduce the notion of an unknotting index for virtual knots. We give some examples of computation by using writhe invariants, and discuss a relationship between the unknotting index and the virtual knot module. In…

Geometric Topology · Mathematics 2017-09-05 K. Kaur , S. Kamada , A. Kawauchi , M. Prabhakar

The braid indices of most links remain unknown as there is no known universal method that can be used to determine the braid index of an arbitrary knot. This is also the case for alternating knots. In this paper, we show that if $K$ is an…

Geometric Topology · Mathematics 2024-08-28 Yuanan Diao , Hugh Morton

We demonstrate that the equivariant unknotting number $\widetilde{u}(K)$ of a strongly invertible knot $K$ is bounded below by the $H$-torsion order $\widetilde{\mathrm{ord}}(K)$ of the involutive Bar-Natan homology…

Geometric Topology · Mathematics 2026-04-13 KeeTaek Kim

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

An equilateral stick number $s_{=}(K)$ of a knot $K$ is defined to be the minimal number of sticks required to construct a polygonal knot of $K$ which consists of equal length sticks. Rawdon and Scharein [12] found upper bounds for the…

Geometric Topology · Mathematics 2014-01-30 Hyoungjun Kim , Sungjong No , Seungsang Oh

We give an upper bound for the dealternating number of a closed 3-braid. As applications, we determine the dealternating numbers, the alternation numbers and the Turaev genera of some closed positive 3-braids. We also show that there exist…

Geometric Topology · Mathematics 2008-12-10 Tetsuya Abe , Kengo Kishimoto

We introduce an alternative stratification of knots: by the size of lattice on which a knot can be first met. Using this classification, we find ratio of unknots and knots with more than 10 minimal crossings inside different lattices and…

Geometric Topology · Mathematics 2023-09-07 E. Lanina , A. Popolitov , N. Tselousov

In this paper, we discuss the region unknotting number of different classes of 2-bridge knots. In particular, we provide region unknotting number for the classes of $2$-bridge knots whose Conway notation is $C(m,\ n), C(m,\ 2,\ m),$ $ C(m,\…

Geometric Topology · Mathematics 2014-07-11 Vikash Siwach , Prabhakar Madeti

We provide linear lower bounds for the signature of positive braids in terms of the three genus of their braid closure. This yields linear bounds for the topological slice genus of knots that arise as closures of positive braids.

Geometric Topology · Mathematics 2015-10-15 Peter Feller

We introduce new sufficient conditions for intrinsic knotting and linking. A graph on n vertices with at least 4n-9 edges is intrinsically linked. A graph on n vertices with at least 5n-14 edges is intrinsically knotted. We also classify…

Geometric Topology · Mathematics 2007-05-23 J. Campbell , T. W. Mattman , R. Ottman , J. Pyzer , M. Rodrigues , S. Williams

A knotted ribbon is one of physical aspect of a knot. A folded ribbon knot is a depiction of a knot obtained by folding a long and thin rectangular strip to become flat. The ribbonlength of a knot type can be defined as the minimum length…

Geometric Topology · Mathematics 2026-02-25 Hyoungjun Kim , Sungjong No , Hyungkee Yoo

We prove that fibred knots cannot be untied with $\bar{t}_{2k}$-moves, for all $k \geq 2$. More generally, we give an upper bound on the number of two strand twist operations that allow to untie a knot with non-trivial HOMFLY polynomial, in…

Geometric Topology · Mathematics 2022-09-15 Lambert A'Campo , Sebastian Baader , Livio Ferretti , Levi Ryffel

We give asymptotically sharp upper bounds for the Khovanov width and the dealternation number of positive braid links, in terms of their crossing number. The same braid-theoretic technique, combined with Ozsv\'ath, Stipsicz, and Szab\'o's…

Geometric Topology · Mathematics 2020-03-26 Sebastian Baader , Peter Feller , Lukas Lewark , Raphael Zentner

We give the first examples of a pair of knots $K_1$,$K_2$ in the 3-sphere for which their unknotting numbers satisfy $u(K_1\#K_2)<u(K_1)+u(K_2)$ . This answers question 1.69(B) from Kirby's problem list, "Problems in low-dimensional…

Geometric Topology · Mathematics 2025-09-16 Mark Brittenham , Susan Hermiller