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Related papers: Legendrian knots and multi-crossings

200 papers

This is a survey paper on Legendrian and transversal knots for Handbook of Knot Theory.

Symplectic Geometry · Mathematics 2007-05-23 John B. Etnyre

An $n$-crossing projection of a link $L$ is a projection of $L$ onto a plane such that $n$ points on $L$ are superimposed on top of each other at every crossing. We prove that for all $k \in \mathbb{N}$ and all links $L$, the inequality…

Geometric Topology · Mathematics 2020-10-30 Anshul Guha

We prove that the class of topological knot types that are both Legendrian simple and satisfy the uniform thickness property (UTP) is closed under cabling. An immediate application is that all iterated cabling knot types that begin with…

Geometric Topology · Mathematics 2016-01-20 Douglas J. LaFountain

It is shown that Legendrian (resp. transverse) cable links in the 3-sphere with its standard tight contact structure, i.e. links consisting of an unknot and a cable of that unknot, are classified by their oriented link type and the…

Symplectic Geometry · Mathematics 2007-12-18 Fan Ding , Hansjörg Geiges

The surgery unknotting number of a Legendrian link is defined as the minimal number of particular oriented surgeries that are required to convert the link into a Legendrian unknot. Lower bounds for the surgery unknotting number are given in…

Symplectic Geometry · Mathematics 2016-01-20 A. Bianca Boranda , Lisa Traynor , Shuning Yan

We use the contact invariant defined in [2] to construct a new invariant of Legendrian knots in Kronheimer and Mrowka's monopole knot homology theory (KHM), following a prescription of Stipsicz and V\'ertesi. Our Legendrian invariant…

Symplectic Geometry · Mathematics 2019-02-12 John A. Baldwin , Steven Sivek

Take a sequence of contactomorphisms of a contact three-manifold that $C^0$-converges to a homeomorphism. If the images of a Legendrian knot limit to a smooth knot under this sequence, we show that it is Legendrian. We prove this by…

Symplectic Geometry · Mathematics 2022-01-13 Georgios Dimitroglou Rizell , Michael G. Sullivan

In this paper we will show how to classify Legendrian and transverse knots in the knot type of "sufficiently positive" cables of a knot in terms of the classification of the underlying knot. We will also completely explain the phenomena of…

Geometric Topology · Mathematics 2021-10-25 Apratim Chakraborty , John B. Etnyre , Hyunki Min

In a recent work of I.\,Dynnikov and M.\,Prasolov a new method of comparing Legendrian knots is proposed. In general, to apply the method requires a lot of technical work. In particular, one needs to search all rectangular diagrams of…

Geometric Topology · Mathematics 2023-06-21 Ivan Dynnikov , Vladimir Shastin

A generic immersion of a circle into a $2$-sphere is often studied as a projection of a knot; it is called a knot projection. A chord diagram is a configuration of paired points on a circle; traditionally, the two points of each pair are…

Geometric Topology · Mathematics 2021-08-24 Noboru Ito , Yusuke Takimura

We show that for a big class of contact manifolds the groups of order $\leq n$ invariants (with values in an arbitrary Abelian group) of Legendrian, of transverse and of framed knots are canonically isomorphic. On the other hand for an…

Symplectic Geometry · Mathematics 2007-05-23 Vladimir Tchernov

Knot and link diagrams are projections of one or more 3-dimensional simple closed curves into $R^2$, such that no more than two points project to the same point in $R^2$. These diagrams are drawings of 4-regular plane multigraphs. Knots are…

Computational Geometry · Computer Science 2019-03-12 Philipp Kindermann , Stephen Kobourov , Maarten Löffler , Martin Nöllenburg , André Schulz , Birgit Vogtenhuber

A triple crossing is a crossing in a projection of a knot or link that has three strands of the knot passing straight through it. A triple crossing projection is a projection such that all of the crossings are triple crossings. We prove…

Geometric Topology · Mathematics 2012-09-05 Colin Adams

In recent joint works of the present author with M.Prasolov and V.Shastin a new technique for distinguishing Legendrian knots has been developed. In this paper the technique is extended further to provide a tool for distinguishing…

Geometric Topology · Mathematics 2019-12-25 Ivan Dynnikov

In this paper we prove that if a knot or link has a sufficiently complicated plat projection, then that plat projection is unique. More precisely, if a knot or link has a $2m$-plat projection, where $m$ is at least four, and height at least…

Geometric Topology · Mathematics 2025-08-12 Nir Lazarovich , Yoav Moriah , Tali Pinsky , Jessica S. Purcell

Determining unknotting numbers is a large and widely studied problem. We consider the more general question of the unknotting number of a spatial graph. We show the unknotting number of spatial graphs is subadditive. Let $g$ be an embedding…

Geometric Topology · Mathematics 2018-05-03 Dorothy Buck , Danielle O'Donnol

In this paper we study Legendrian knots in the knot types of satellite knots. In particular, we classify Legendrian Whitehead patterns and learn a great deal about Legendrian braided patterns. We also show how the classification of…

Geometric Topology · Mathematics 2016-08-22 John Etnyre , Vera Vértesi

A quadruple crossing is a crossing in a projection of a knot or link that has four strands of the knot passing straight through it. A quadruple crossing projection is a projection such that all of the crossings are quadruple crossings. In a…

Geometric Topology · Mathematics 2019-02-20 Colin Adams

In this paper, the support genus of all Legendrian right handed trefoil knots and some other Legendrian knots is computed. We give examples of Legendrian knots in the three-sphere with the standard contact structure which have positive…

Geometric Topology · Mathematics 2011-01-28 Youlin Li , Jiajun Wang

We study Legendrian knots in a cabled knot type. Specifically, given a topological knot type K, we analyze the Legendrian knots in knot types obtained from K by cabling, in terms of Legendrian knots in the knot type K. As a corollary of…

Symplectic Geometry · Mathematics 2007-06-13 John B. Etnyre , Ko Honda