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Related papers: Invariants of Legendrian knots

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We introduce topological invariants of knots and braid conjugacy classes, in the form of differential graded algebras, and present an explicit combinatorial formulation for these invariants. The algebras conjecturally give the relative…

Geometric Topology · Mathematics 2014-11-11 Lenhard Ng

We show that there exists an infinite family of pairwise non-isotopic Legendrian knots in the standard contact 3-sphere whose Stein traces are equivalent. This is the first example of such phenomenon. Different constructions are developed…

Symplectic Geometry · Mathematics 2026-02-10 Roger Casals , John Etnyre , Marc Kegel

We use monopole Floer homology for sutured manifolds to construct invariants of Legendrian knots in a contact 3-manifold. These invariants assign to a knot K in Y elements of the monopole knot homology KHM(-Y,K), and they strongly resemble…

Symplectic Geometry · Mathematics 2015-06-10 Steven Sivek

In this short note, we construct a family of non-regular, and therefore non-decomposable, Lagrangian concordances between Lagrangian fillable Legendrian knots in the standard contact 3-dimensional sphere. More precisely, for every…

Symplectic Geometry · Mathematics 2025-09-18 Georgios Dimitroglou Rizell , Roman Golovko

Linearized Legendrian contact homology (LCH) and bilinearized LCH are important homological invariants for Legendrian submanifolds in contact geometry. For legendrian knots in $\mathbb{R}^3$, very little was previously known about the…

Symplectic Geometry · Mathematics 2025-10-28 Frédéric Bourgeois , Salammbo Connolly

In this article we define Lagrangian concordance of Legendrian knots, the analogue of smooth concordance of knots in the Legendrian category. In particular we study the relation of Lagrangian concordance under Legendrian isotopy. The focus…

Symplectic Geometry · Mathematics 2014-10-01 Baptiste Chantraine

We show that there exists a Legendrian knot with maximal Thurston-Bennequin invariant whose contact homology is trivial. We also provide another Legendrian knot which has the same knot type and classical invariants but nonvanishing contact…

Symplectic Geometry · Mathematics 2017-08-03 Steven Sivek

Using convex surfaces and Kanda's classification theorem, we classify Legendrian isotopy classes of Legendrian linear curves in all tight contact structures on $T^3$. Some of the knot types considered in this article provide new examples of…

Geometric Topology · Mathematics 2007-05-23 Paolo Ghiggini

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

Suppose that L is a null--homologous Legendrian knot in a contact 3--manifold. We determine the connection between the sutured invariant of the complement of L and the Legendrian invariant defined by Lisca, Ozsvath, Stipsicz and Szabo. In…

Symplectic Geometry · Mathematics 2008-12-30 Andras I. Stipsicz , Vera Vertesi

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

We investigate an equivalence relation on Legendrian knots in the standard contact three-space defined by the existence of an interpolating zigzag of Lagrangian cobordisms. We compare this relation, restricted to genus-$0$ surfaces, to…

Symplectic Geometry · Mathematics 2023-08-07 Joshua M. Sabloff , David Shea Vela-Vick , C. -M. Michael Wong , Angela Wu

We present examples of Legendrian knots in $\mathbb{R}^3$ that have linearized Legendrian contact homology over $\mathbb{Z}$ containing torsion. As a consequence, we show that there exist augmentations of Legendrian knots over $\mathbb{Z}$…

Symplectic Geometry · Mathematics 2024-07-18 Robert Lipshitz , Lenhard Ng

In this note, we observe that the hat version of the Heegaard Floer invariant of Legendrian knots in contact three-manifolds defined by Lisca-Ozsvath-Stipsicz-Szabo can be combinatorially computed. We rely on Plamenevskaya's combinatorial…

Geometric Topology · Mathematics 2021-03-16 Dongtai He , Linh Truong

We present an atlas of Legendrian knots in standard contact three-space. This gives a conjectural Legendrian classification for all knots with arc index at most 9, including alternating knots through 7 crossings and nonalternating knots…

Symplectic Geometry · Mathematics 2013-05-08 Wutichai Chongchitmate , Lenhard Ng

We provide a translation between Chekanov's combinatorial theory for invariants of Legendrian knots in the standard contact R^3 and a relative version of Eliashberg and Hofer's Contact Homology. We use this translation to transport the idea…

Symplectic Geometry · Mathematics 2007-05-23 John B. Etnyre , Lenhard L. Ng , Joshua M. Sabloff

Associated to Legendrian links in the standard contact three-space, Ruling polynomials are Legendrian isotopy invariants, which also compute augmentation numbers, that is, the points-counting of augmentation varieties for Legendrian links…

Symplectic Geometry · Mathematics 2017-07-18 Tao Su

This paper is an overview of the idea of using contact geometry to construct invariants of immersions and embeddings. In particular, it discusses how to associate a contact manifold to any manifold and a Legendrian submanifold to an…

Geometric Topology · Mathematics 2007-05-23 Tobias Ekholm , John B. Etnyre

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

In this note we show that $+1$-contact surgery on distinct Legendrian knots frequently produces contactomorphic manifolds. We also give examples where this happens for $-1$-contact surgery. As an amusing corollary we find overtwisted…

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