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Related papers: New examples of tunnel number subadditivity

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It is a consequence of theorems of Gordon-Reid [Tangle decompositions of tunnel number one knots and links, J. Knot Theory and its Ramifications, 4 (1995) 389-409] and Thompson [Thin position and bridge number for knots in the 3-sphere,…

Geometric Topology · Mathematics 2014-11-11 Hiroshi Goda , Martin Scharlemann , Abigail Thompson

We present computational results about quasi-alternating knots and links and odd homology obtained by looking at link families in the Conway notation. More precisely, we list quasi-alternating links up to 12 crossings and the first examples…

Geometric Topology · Mathematics 2014-04-01 Slavik Jablan , Radmila Sazdanović

We prove a simple necessary and sufficient condition for a two-bridge knot K(p,q) to be quasipositive, based on the continued fraction expansion of p/q. As an application, coupled with some classification results in contact and symplectic…

Geometric Topology · Mathematics 2025-05-09 Burak Ozbagci

This paper introduces a new approach to finding knots and links with hidden symmetries using "hidden extensions", a class of hidden symmetries defined here. We exhibit a family of tangle complements in the ball whose boundaries have…

Geometric Topology · Mathematics 2016-09-20 Eric Chesebro , Jason DeBlois

We introduce and study knots and links in 2-dimensional complexes. In particular, we define linking numbers for oriented two-component links in 2-complexes and a Kauffman-type bracket polynomial for links in 2-complexes. We also discuss…

Geometric Topology · Mathematics 2023-06-13 Vladimir Turaev

A torti-rational knot, denoted by K(2a,b|r), is a knot obtained from the 2-bridge link B(2a,b) by applying Dehn twists an arbitrary number of times, r, along one component of B(2a,b). We determine the genus of K(2a,b|r) and solve a question…

Geometric Topology · Mathematics 2008-10-23 M. Hirasawa , K. Murasugi

The Wirtinger number of a virtual link is the minimum number of generators of the link group over all meridional presentations in which every relation is an iterated Wirtinger relation arising in a diagram. We prove that the Wirtinger…

Geometric Topology · Mathematics 2019-11-12 Puttipong Pongtanapaisan

We construct an invariant of virtual knots which is a sliceness obstruction and sensitive to the $\Delta$-move. This invariants works if $\Z_{2}\oplus \Z_{2}$-index of chords is present.

Geometric Topology · Mathematics 2022-01-04 Vassily Olegovich Manturov

In this paper, we extend the theory of planar pseudo knots to the theories of annular and toroidal pseudo knots. Pseudo knots are defined as equivalence classes under Reidemeister-like moves of knot diagrams characterized by crossings with…

Geometric Topology · Mathematics 2024-09-09 Ioannis Diamantis , Sofia Lambropoulou , Sonia Mahmoudi

We study petal diagrams of knots, which provide a method of describing knots in terms of permutations in a symmetric group $S_{2n+1}$. We define two classes of moves on such permutations, called trivial petal additions and crossing…

Geometric Topology · Mathematics 2018-12-24 Leslie Colton , Cory Glover , Mark Hughes , Samantha Sandberg

We develop a model characterizing all possible knots and links arising from recombination starting with a twist knot substrate, extending previous work of Buck and Flapan. We show that all knot or link products fall into three…

Geometric Topology · Mathematics 2015-05-19 Dorothy Buck , Karin Valencia

For prime knots $K_1$ and $K_2$, we write $K_1 \geq K_2$ if there is an epimorphism from the knot group of $K_1$ to that of $K_2$ which preserves the meridian. We construct a family of pairs of knots with $K_1 \geq K_2$ such that an…

Geometric Topology · Mathematics 2025-02-13 Teruaki Kitano , Yasuharu Nakae

In this paper we study the theory of knotoids and braidoids and the theory of pseudo knotoids and pseudo braidoids on the torus T. In particular, we introduce the notion of {\it mixed knotoids} in $S^2$, that generalize the notion of mixed…

Geometric Topology · Mathematics 2021-03-31 Ioannis Diamantis

We show there exists a linear embedding of $K_{3,3,1}$ with n nontrivial 2-component links if and only if n = 1, 2, 3, 4, or 5.

Geometric Topology · Mathematics 2012-07-04 Ramin Naimi , Elena Pavelescu

To each rail knotoid we associate two unoriented knots along with their oriented counterparts, thus deriving invariants for rail knotoids based on these associations. We then translate them to invariants of rail isotopy for rail arcs.

Geometric Topology · Mathematics 2021-11-04 Dimitrios Kodokostas , Sofia Lambropoulou

Call a smooth knot (or smooth link) in the unit sphere in $\mathbb{C}^2$ analytic (respectively, smoothly analytic) if it bounds a complex curve (respectively, a smooth complex curve) in the complex ball. Let $K$ be a smoothly analytic…

Geometric Topology · Mathematics 2017-02-20 Burglind Jöricke

This note shows that if two elements of equal trace (e.g., conjugate elements) generate an arithmetic two-bridge knot or link group, then the elements are parabolic. This includes the figure-eight knot and Whitehead link groups. Similarly,…

Geometric Topology · Mathematics 2013-01-29 Jason Callahan

Let M be $S^3$, $S^1\times S^2$, or a lens space L(p,q), and let k be a (1,1)-knot in M, i.e., a knot which is of 1-bridge with respect to a Heegaard torus. We show that if there is a closed meridionally incompressible surface in the…

Geometric Topology · Mathematics 2009-09-29 Mario Eudave-Munoz

We give an obstruction to unknotting a knot by adding a twisted band, derived from Heegaard Floer homology.

Geometric Topology · Mathematics 2010-09-20 Yuanyuan Bao

This paper investigates the relationship between the signature and the crossing number of knots and links. We refine existing theorems and provide a comprehensive classification of links with specific properties, particularly those with…

Geometric Topology · Mathematics 2024-10-02 Kai Ishihara , Kei Okada , Koya Shimokawa