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Related papers: On Legendrian knots and polynomial invariants

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Examples are given of prime Legendrian knots in the standard contact 3-space that have arbitrarily many distinct Chekanov polynomials, refuting a conjecture of Lenny Ng. These are constructed using a new `Legendrian tangle replacement'…

Geometric Topology · Mathematics 2014-11-11 Paul Melvin , Sumana Shrestha

We show that in $(S^3,\xi_{std})$ if $K$ is a non-trivial knot that realizes the three-dimensional Thurston-Bennequin bound (i.e. $K$ has a Legendrian representative $\Lambda$ with $tb(\Lambda)-rot(\Lambda)=2g(K)-1$), then $K$ has a…

Geometric Topology · Mathematics 2024-10-31 Zhenkun Li , Shunyu Wan

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 give explicit formulas and algorithms for the computation of the Thurston-Bennequin invariant of a nullhomologous Legendrian knot on a page of a contact open book and on contact Heegaard surfaces. Furthermore, we extend the results to…

Geometric Topology · Mathematics 2026-02-10 Sebastian Durst , Marc Kegel , Mirko Klukas

We define invariants of null--homologous Legendrian and transverse knots in contact 3--manifolds. The invariants are determined by elements of the knot Floer homology of the underlying smooth knot. We compute these invariants, and show that…

Symplectic Geometry · Mathematics 2009-04-21 Paolo Lisca , Peter Ozsváth , András I. Stipsicz , Zoltán Szabó

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

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

Theory is developed for linear-quadratic at infinity generating families for Legendrian knots in R^3. It is shown that the unknot with maximal Thurston--Bennequin invariant of -1 has a unique linear-quadratic at infinity generating family,…

Geometric Topology · Mathematics 2009-04-20 Jill Jordan , Lisa Traynor

The slice-Bennequin inequality states an upper bound for the self-linking number of a knot in terms of its four-ball genus. The $s$-Bennequin and $\tau$-Bennequin inequalities provide upper bounds on the self-linking number of a knot in…

Geometric Topology · Mathematics 2020-10-06 Elaina Aceves , Keiko Kawamuro , Linh Truong

In this paper, we introduce a rational $\tau$ invariant for rationally null-homologous knots in contact 3-manifolds with nontrivial Ozsv\'{a}th-Szab\'{o} contact invariants. Such an invariant is an upper bound for the sum of rational…

Geometric Topology · Mathematics 2017-08-14 Youlin Li , Zhongtao Wu

We present new families of examples of non-simple prime Legendrian and transversal knots in tight Lens spaces, which demonstrate that the botany of Legendrians in Lens space is rich. In fact, there are more non-isotopic Legendrians that are…

Geometric Topology · Mathematics 2025-12-29 Ipsita Datta , Tanushree Shah

If a Legendrian knot $\Lambda$ in the standard contact 3-sphere bounds an orientable exact Lagrangian surface $\Sigma$ in the standard symplectic 4-ball, then the genus of $\Sigma$ is equal to the slice genus of (the smooth knot underlying)…

Symplectic Geometry · Mathematics 2018-03-16 Tolga Etgü

We define ruling invariants for even-valence Legendrian graphs in standard contact three-space. We prove that rulings exist if and only if the DGA of the graph, introduced by the first two authors, has an augmentation. We set up the usual…

Symplectic Geometry · Mathematics 2019-11-21 Byung Hee An , Youngjin Bae , Tamás Kálmán

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

All knots in $R^3$ possess Seifert surfaces, and so the classical Thurston-Bennequin and rotation (or Maslov) invariants for Legendrian knots in a contact structure on $R^3$ can be defined. The definitions extend easily to null-homologous…

Geometric Topology · Mathematics 2015-02-27 Paul A. Schweitzer SJ , Fábio S. Souza

We derive a relative version of the slicing Bennequin inequalities for cobordant Legendrian knots, and review a few proofs of the result.

Symplectic Geometry · Mathematics 2011-09-12 Georgi D. Gospodinov

We extend knot contact homology to a theory over the ring $\mathbb{Z}[\lambda^{\pm 1},\mu^{\pm 1}]$, with the invariant given topologically and combinatorially. The improved invariant, which is defined for framed knots in $S^3$ and can be…

Geometric Topology · Mathematics 2008-06-11 Lenhard Ng

We show that any knot which is smoothly the closure of a 3-braid cannot be Lagrangian concordant to and from the maximum Thurston-Bennequin Legendrian unknot except the unknot itself. Our obstruction comes from drawing the Weinstein…

Symplectic Geometry · Mathematics 2022-04-01 Angela Wu

For a knot in the 3-sphere, the Upsilon invariant is a piecewise linear function defined on the interval [0,2]. For an L-space knot, the Upsilon invariant is determined only by the Alexander polynomial of the knot. We exhibit infinitely…

Geometric Topology · Mathematics 2024-03-26 Masakazu Teragaito

We give criteria for an invariant of lens space links to bound the maximal self-linking number in certain tight contact lens spaces. As a corollary we extend the Franks-Williams-Morton inequality to the setting of lens spaces.

Geometric Topology · Mathematics 2011-11-11 Christopher R. Cornwell