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Related papers: Legendrian knots in overtwisted contact structures

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We study the unwrapped Fukaya category of Lagrangian branes ending on a Legendrian knot. Our knots live at contact infinity in the cotangent bundle of a surface, the Fukaya category of which is equivalent to the category of constructible…

Symplectic Geometry · Mathematics 2016-11-01 Vivek Shende , David Treumann , Eric Zaslow

Ozsv\'ath and Stipsicz showed that some Eliashberg-Chekanov twist knots, which are Whitehead doubles of the unknot, are not Legendrian simple. We extend their result by considering some Whitehead doubles of the trefoil: Using properties of…

Geometric Topology · Mathematics 2025-12-22 Saliha Kıvanç

We prove that the LOSS and GRID invariants of Legendrian links in knot Floer homology behave in certain functorial ways with respect to decomposable Lagrangian cobordisms in the symplectization of the standard contact structure on…

Geometric Topology · Mathematics 2019-07-30 John A. Baldwin , Tye Lidman , C. -M. Michael Wong

The conormal Lagrangian $L_K$ of a knot $K$ in $\mathbb{R}^3$ is the submanifold of the cotangent bundle $T^* \mathbb{R}^3$ consisting of covectors along $K$ that annihilate tangent vectors to $K$. By intersecting with the unit cotangent…

Symplectic Geometry · Mathematics 2017-05-24 Kai Cieliebak , Tobias Ekholm , Janko Latschev , Lenhard Ng

We define a new algebraic structure called Legendrian racks or racks with Legendrian structure, motivated by the front-projection Reidemeister moves for Legendrian knots. We provide examples of Legendrian racks and use these algebraic…

Geometric Topology · Mathematics 2021-01-26 Jose Ceniceros , Mohamed Elhamdadi , Sam Nelson

We prove the equivalence of the invariants EH(L) and LOSS-(L) for oriented Legendrian knots L in the 3-sphere equipped with the standard contact structure, partially extending a previous result by Stipsicz and Vertesi. In the course of the…

Geometric Topology · Mathematics 2014-04-07 Marco Golla

We investigate the question of the existence of a Lagrangian concordance between two Legendrian knots in $\mathbb{R}^3$. In particular, we give obstructions to a concordance from an arbitrary knot to the standard Legendrian unknot, in terms…

Symplectic Geometry · Mathematics 2016-05-04 Christopher R. Cornwell , Lenhard Ng , Steven Sivek

We define a differential graded algebra associated to Legendrian knots in Seifert fibered spaces with transverse contact structures. This construction is distinguished from other combinatorial realizations of contact homology invariants by…

Symplectic Geometry · Mathematics 2010-12-14 Joan E. Licata , Joshua M. Sabloff

We study the singularities of Legendrian subvarieties of contact manifolds in the complex-analytic category and prove two rigidity results. The first one is that Legendrian singularities with reduced tangent cones are contactomorphically…

Algebraic Geometry · Mathematics 2023-06-22 Jun-Muk Hwang

We demonstrate that the contact cosmetic surgery conjecture holds true for all non-trivial Legendrian knots, with the possible exception of Lagrangian slice knots. We also discuss the contact cosmetic surgeries on Legendrian unknots and…

Geometric Topology · Mathematics 2025-03-07 John B. Etnyre , Tanushree Shah

If a characteristic class for two vector bundles over the same base space does not coincide, then the bundles are not isomorphic. We give under rather common assumptions a lower bound on the topological dimension of the set of all points in…

Algebraic Topology · Mathematics 2013-12-17 Maciej Starostka , Nils Waterstraat

This is an introduction to Legendrian contact homology and the Chekanov-Eliashberg differential graded algebra, with a focus on the setting of Legendrian knots in $\mathbb{R}^3$. This is the published version of the paper, but with a…

Symplectic Geometry · Mathematics 2023-04-21 John B. Etnyre , Lenhard L. Ng

We resolve a case of the oriented knot complement conjecture by showing that knots in an orientable circle bundle $N$ over a genus $g \geq 2$ surface $S$ are determined by their complements. We apply this to the setting of canonical knots…

Geometric Topology · Mathematics 2024-01-08 Tommaso Cremaschi , Andrew Yarmola

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

In this paper, we show that any topological knot or link in $S^1 \times S^2$ sits on a planar page of an open book decomposition whose monodromy is a product of positive Dehn twists. As a consequence, any knot or link type in $S^1 \times…

Geometric Topology · Mathematics 2020-05-11 Sinem Onaran

Legendrian Contact Homology (LCH) and its augmentations are important invariants of Legendrian submanifolds, and for Legendrian knots in the standard contact 3-space in particular. We increase understanding of the algebraic structure of LCH…

Symplectic Geometry · Mathematics 2025-09-03 Jiajie Ma , Joshua M. Sabloff

By proving a connected sum formula for the Legendrian invariant $\lambda_+$ in knot Floer homology we exhibit infinitely many transversely non simple knots.

Symplectic Geometry · Mathematics 2016-01-20 Vera Vértesi

We show that the germ of the contact structure surrounding a certain kind of convex hypersurfaces is overtwisted. We then find such hypersurfaces close to any plastikstufe with toric core so that these imply overtwistedness. All proofs in…

Symplectic Geometry · Mathematics 2025-11-05 River Chiang , Klaus Niederkrüger-Eid

For any Legendrian knot or link in $\mathbb{R}^3$, we construct an $L_\infty$ algebra that can be viewed as an extension of the Chekanov-Eliashberg differential graded algebra. The $L_\infty$ structure incorporates information from rational…

Symplectic Geometry · Mathematics 2025-07-21 Lenhard Ng

In this paper we prove the presence of an embedded plastikstufe implies overtwistedness of the contact structure in any dimension. Moreover, we show in dimension 5 that the presence of an embedded bordered Legendrian open book (bLob) also…

Symplectic Geometry · Mathematics 2017-06-28 Yang Huang