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Related papers: Legendrian knots in overtwisted contact structures

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We prove gluing theorems for tight contact structures. In particular, we rederive (as special cases) gluing theorems due to Colin and Makar-Limanov, and present an algorithm for determining whether a given contact structure on a handlebody…

Geometric Topology · Mathematics 2007-05-23 Ko Honda

It was shown in arXiv:1208.5742 that any smooth knot can be represented by an \"ubercrossing projection, i.e. a knot projection with no crossings aside from a single multi-crossing. We extend this idea to Legendrian knots and investigate…

Geometric Topology · Mathematics 2024-05-09 Amit Kumar , Jake Murphy , Brian Naff

We explore the construction of Legendrian spheres in contact manifolds of any dimension. Two constructions involving open books work in any contact manifold, while one introduced by Ekholm works only in $\mathbb{R}^{2n+1}$. We show that…

Symplectic Geometry · Mathematics 2025-06-25 Agniva Roy

A correspondence is studied by H. Matsuda between front projections of Legendrian links in the standard contact structure for 3-space and rectangular diagrams. In this paper, we introduce braided rectangular diagrams, and study a…

Geometric Topology · Mathematics 2007-08-20 Hiroshi Matsuda , William W. Menasco

We study Legendrian and transverse realizations of the negative torus knots $T_{(p,-q)}$ in all contact structures on the $3$-sphere. We give a complete classification of the strongly non-loose transverse realizations and the strongly…

Geometric Topology · Mathematics 2023-03-02 Irena Matkovič

In this article, we explore a polynomial invariant for Legendrian knots which is a natural extension of Jones polynomial for (topological) knots. To this end, a new type of skein relation is introduced for the front projections of…

Geometric Topology · Mathematics 2025-10-07 Dheeraj Kulkarni , Monika Yadav

We classify Legendrian rational unknots with tight complements in the lens spaces L(p,1) up to coarse equivalence. As an example of the general case, this classification is also worked out for L(5,2). The knots are described explicitly in a…

Symplectic Geometry · Mathematics 2018-03-22 Hansjörg Geiges , Sinem Onaran

In 1997, Chekanov gave the first example of a Legendrian nonsimple knot type: the $m(5_2)$ knot. Epstein, Fuchs, and Meyer extended his result by showing that there are at least $n$ different Legendrian representatives with maximal…

Symplectic Geometry · Mathematics 2013-05-08 John B. Etnyre , Lenhard L. Ng , Vera Vertesi

In the present paper a criteria for a rectangular diagram to admit a simplification is given in terms of Legendrian knots. It is shown that there are two types of simplifications which are mutually independent in a sense. A new proof of the…

Geometric Topology · Mathematics 2013-10-22 Ivan Dynnikov , Maxim Prasolov

It is known that any tame hyperbolic 3-manifold with infinite volume and a single end is the geometric limit of a sequence of finite volume hyperbolic knot complements. Purcell and Souto showed that if the original manifold embeds in the…

Geometric Topology · Mathematics 2023-06-22 Urs Fuchs , Jessica S. Purcell , John Stewart

We resolve a question of Fuchs and Tabachnikov by showing that there is a Legendrian knot in standard contact three-space with zero Maslov number which is not Legendrian isotopic to its mirror. The proof uses the differential graded…

Geometric Topology · Mathematics 2007-05-23 Lenhard L. Ng

We establish an upper bound for the Thurston-Bennequin number of a Legendrian link using the Khovanov homology of the underlying topological link. This bound is sharp in particular for all alternating links, and knots with nine or fewer…

Geometric Topology · Mathematics 2014-10-01 Lenhard Ng

We give a combinatorial description of the Legendrian differential graded algebra associated to a Legendrian knot in PxR, where P is a punctured Riemann surface. As an application we show that for any integer k and any homology class h in…

Symplectic Geometry · Mathematics 2017-05-17 Johan Björklund

For a smooth compact submanifold $K$ of a Riemannian manifold $Q$, its unit conormal bundle $\Lambda_K$ is a Legendrian submanifold of the unit cotangent bundle of $Q$ with a canonical contact structure. Using pseudo-holomorphic curve…

Symplectic Geometry · Mathematics 2025-05-26 Yukihiro Okamoto

Legendrian contact homology (LCH) and its associated differential graded algebra are powerful non-classical invariants of Legendrian knots. Linearization makes the LCH computationally tractable at the expense of discarding nonlinear (and…

Symplectic Geometry · Mathematics 2009-01-06 Gokhan Civan , John B. Etnyre , Paul Koprowski , Joshua M. Sabloff , Alden Walker

We introduce a simple combinatorial way, which we call a rectangular diagram of a surface, to represent a surface in the three-sphere. It has a particularly nice relation to the standard contact structure on $\mathbb S^3$ and to rectangular…

Geometric Topology · Mathematics 2017-09-13 Ivan Dynnikov , Maxim Prasolov

Final revision. To appear in the Journal of Differential Geometry. This paper studies knots that are transversal to the standard contact structure in $\reals^3$, bringing techniques from topological knot theory to bear on their transversal…

Geometric Topology · Mathematics 2007-05-23 Joan S. Birman , Nancy C. Wrinkle

Let $\Lambda$ be a Legendrian in the jet space of some manifold $X$. To a generating family presentation of $\Lambda$, we associate a constructible sheaf on $X \times \mathbb{R}$ whose singular support at infinity is $\Lambda$, and such…

Symplectic Geometry · Mathematics 2018-09-11 Vivek Shende

We define an invariant of Legendrian links in the double-point enhanced grid homology of a link, and prove that it obstructs decomposable Lagrangian cobordisms in the symplectization of the standard contact structure on $\mathbb R^3$.

Geometric Topology · Mathematics 2025-05-13 Ashton Lewis , Zachary Ojakli , Ina Petkova , Benjamin Shapiro

We establish a long exact sequence for Legendrian submanifolds L in P x R, where P is an exact symplectic manifold, which admit a Hamiltonian isotopy that displaces the projection of L off of itself. In this sequence, the singular homology…

Symplectic Geometry · Mathematics 2019-12-19 Tobias Ekholm , John B. Etnyre , Joshua M. Sabloff