English
Related papers

Related papers: Folded ribbon knots in the plane

200 papers

We apply Bayesian optimization and reinforcement learning to a problem in topology: the question of when a knot bounds a ribbon disk. This question is relevant in an approach to disproving the four-dimensional smooth Poincar\'e conjecture;…

Geometric Topology · Mathematics 2025-06-16 Sergei Gukov , James Halverson , Ciprian Manolescu , Fabian Ruehle

We model proteins with intramolecular bonds, such as disulfide bridges, using the concept of bonded knots -- closed loops in three-dimensional space equipped with additional bonds that connect different segments of the knot. We extend the…

Geometric Topology · Mathematics 2025-02-27 Boštjan Gabrovšek , Matic Simonič

We explore free knot diagrams, which are projections of knots into the plane which don't record over/under data at crossings. We consider the combinatorial question of which free knot diagrams give which knots and with what probability.…

Geometric Topology · Mathematics 2020-11-25 Andrew Ducharme , Emily Peters

Ribbons are long narrow strips possessing three distinct material length scales (thickness, width, and length) which allow them to produce unique shapes unobtainable by wires or filaments. For example when a ribbon has half a twist and is…

Fluid Dynamics · Physics 2016-02-04 Lyndon Koens , Eric Lauga

The classical Thistlethwaite theorem for links can be phrased as asserting that the Kauffman bracket of a link can be obtained from an evaluation of the Bollob\'as-Riordan polynomial of a ribbon graph associated to one of the link's…

Geometric Topology · Mathematics 2024-12-18 Sergei Chmutov , Qingying Deng , Joanna A. Ellis-Monaghan , Sergei Lando , Wout Moltmaker

A flip in a plane spanning tree $T$ is the operation of removing one edge from $T$ and adding another edge such that the resulting structure is again a plane spanning tree. For trees on a set of points in convex position we study two…

Computational Geometry · Computer Science 2025-08-22 Oswin Aichholzer , Joseph Dorfer , Birgit Vogtenhuber

Given a knot in $S^3$, one can associate to it a surface diffeomorphism in two different ways. First, an arbitrary knot in $S^{3}$ can be represented by braids, which can be thought of as diffeomorphisms of punctured disks. Second, if the…

We study simple, knotted and linked torus windings that are made of tubes of finite thickness. Knots which have the shortest rope length are often denoted ideal structures. Conventionally, the ideal structure are found by rope shortening…

General Physics · Physics 2015-06-16 Kasper W Olsen , Jakob Bohr

A knot type is exchange reducible if an arbitrary closed n-braid representative can be changed to a closed braid of minimum braid index by a finite sequence of braid isotopies, exchange moves and +/- destabilizations. In the manuscript [J…

Geometric Topology · Mathematics 2014-11-11 William W Menasco

The aim of this paper is to realise the techniques of picture-valued invariants and invariants valued in free groups for long knots in the full torus. Such knots and links are of a particular interest because of their relation to Legendrian…

Algebraic Topology · Mathematics 2021-09-16 Sera Kim , Seongjeong Kim , Vassily Olegovich Manturov

In this paper we present a detailed study of \emph{bonded knots} and their related structures, integrating recent developments into a single framework. Bonded knots are classical knots endowed with embedded bonding arcs modeling physical or…

Geometric Topology · Mathematics 2025-12-09 Ioannis Diamantis , Louis H. Kauffman , Sofia Lambropoulou

Let $\mbox{Len}(K)$ be the minimum length of a knot on the cubic lattice (namely the minimum length necessary to construct the knot in the cubic lattice). This paper provides upper bounds for $\mbox{Len}(K)$ of a nontrivial knot $K$ in…

Geometric Topology · Mathematics 2014-11-10 Kyungpyo Hong , Hyoungjun Kim , Sungjong No , Seungsang Oh

The $T$-genus of a knot is the minimal number of borromean-type triple points on a normal singular disk with no clasp bounded by the knot; it is an upper bound for the slice genus. Kawauchi, Shibuya and Suzuki characterized the slice knots…

Geometric Topology · Mathematics 2024-10-14 Delphine Moussard

Ribbon concordance gives a partial order on knot types, and applying a knot homology functor to a ribbon concordance gives an inclusion of the homologies. The question of the existence of global ribbon minima in each concordance class is a…

Geometric Topology · Mathematics 2026-02-16 Andrew Lobb

The ropelength of a knot is the quotient of its length by its thickness. We consider a family of energy functions for knots, depending on a power p, which approach ropelength as p increases. We describe a numerically computed trefoil knot…

Geometric Topology · Mathematics 2007-05-23 John M Sullivan

We show that the triple-crossing number of any knot is greater or equal to twice its (canonical) genus and we show an even stronger bound in the case of links. As an application we show that this bound is strong enough to obtain the…

Geometric Topology · Mathematics 2020-11-10 Michal Jablonowski

We establish a Kauffman-Murasugi-Thistlethwaite-type theorem for alternating knots in a solid torus. Specifically, we show that any dotted-reduced alternating diagram of a knot in a handlebody realizes the minimal crossing number, and that…

Geometric Topology · Mathematics 2026-01-30 Lizzie Buchanan , Tanushree Shah

We define a knot to be $\gamma_0$-sharp if its Seifert genus is detected by the concordance invariant $\gamma_0$, which arises from the immersed curve formalism in bordered Heegaard Floer homology. We show that a connected sum of…

Geometric Topology · Mathematics 2025-07-29 Jennifer Hom , JungHwan Park

In this paper, we determine geometric information on slope lengths of a large class of knots in the 3-sphere, based only on diagrammatical properties of the knots. In particular, we show such knots have meridian length strictly less than 4,…

Geometric Topology · Mathematics 2008-07-23 Jessica S. Purcell

We present new computations of tight shapes obtained using the constrained gradient descent code RIDGERUNNER for 544 composite knots with 12 and fewer crossings, expanding our dataset to 943 knots and links. We use the new data set to…

Differential Geometry · Mathematics 2015-05-30 Jason Cantarella , Al LaPointe , Eric Rawdon