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Related papers: A note on knots with H(2)-unknotting number one

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We present a topological interpretation of knot and braid contact homology in degree zero, in terms of cords and skein relations. This interpretation allows us to extend the knot invariant to embedded graphs and higher-dimensional knots. We…

Geometric Topology · Mathematics 2014-11-11 Lenhard Ng

We construct $S^r$-colored knot Floer homologies and prove that they satisfy categorified recurrence relations. The associated Euler characteristic implies $q$-holonomicity of the corresponding sequence of colored Alexander polynomials, in…

Geometric Topology · Mathematics 2025-03-18 Benjamin Cooper , Robert Deyeso

We establish homotopy ribbon concordance obstructions coming from the Blanchfield form and Levine-Tristram signatures. Then, as an application of twisted Alexander polynomials, we show that for every knot K with nontrivial Alexander…

Geometric Topology · Mathematics 2022-09-05 Stefan Friedl , Takahiro Kitayama , Lukas Lewark , Matthias Nagel , Mark Powell

We consider the question, asked by Friedl, Livingston and Zentner, of which sums of torus knots are concordant to alternating knots. After a brief analysis of the problem in its full generality, we focus on sums of two torus knots. We…

Geometric Topology · Mathematics 2019-01-17 Paolo Aceto , Antonio Alfieri

In this note, we give a short proof that knot Floer thickness is a lower bound on the dealternating number of a knot. The result is originally due to work of Abe and Kishimoto, Lowrance, and Turaev. Our proof is a modification of the…

Geometric Topology · Mathematics 2022-05-18 Linh Truong

Let $K_m$ be the result of applying $m$ full twists to $n$ parallel strands in a knot $K$. We prove that extremal knot Floer homologies of $K_m$ stabilize as $m$ goes to infinity.

Geometric Topology · Mathematics 2025-09-04 Soheil Azarpendar

Ozsvath and Szabo defined an analog of the Froyshov invariant in the form of a correction term for the grading in Heegaard Floer homology. Applying this to the double cover of the 3-sphere branched over a knot K, we obtain an invariant…

Geometric Topology · Mathematics 2016-09-07 Ciprian Manolescu , Brendan Owens

We prove for the first time that knot Floer homology and Khovanov homology can detect non-fibered knots, and that HOMFLY homology detects infinitely many such knots; these theories were previously known to detect a mere six knots, all…

Geometric Topology · Mathematics 2025-01-29 John A. Baldwin , Steven Sivek

In 2005 Dunfield, Gukov and Rasmussen conjectured an existence of the spectral sequence from the reduced triply graded Khovanov-Rozansky homology of a knot to its knot Floer homology defined by Ozsv\'ath and Szab\'o. The main result of this…

Geometric Topology · Mathematics 2025-01-20 Anna Beliakova , Krzysztof K. Putyra , Louis-Hadrien Robert , Emmanuel Wagner

In joint work with J. Rasmussen, we gave an interpretation of Heegaard Floer homology for manifolds with torus boundary in terms of immersed curves in a punctured torus. In particular, knot Floer homology is captured by this invariant.…

Geometric Topology · Mathematics 2023-06-14 Jonathan Hanselman , Liam Watson

For strongly invertible knots, we define an involutive version of Khovanov homology, and from it derive a pair of integer-valued invariants $(\underline{s}, \bar{s})$, which is an equivariant version of Rasmussen's $s$-invariant. Using…

Geometric Topology · Mathematics 2025-11-26 Taketo Sano

We show that the bridge number of a $t$ bridge knot in $S^3$ with respect to an unknotted genus $t$ surface is bounded below by a function of the distance of the Heegaard splitting induced by the $t$ bridges. It follows that for any natural…

Geometric Topology · Mathematics 2007-05-23 Jesse Johnson , Abigail Thompson

Ng constructed an invariant of knots in ${\mathbb{R}}^3$, a combinatorial knot contact homology. Extending his study, we construct an invariant of surface-knots in ${\mathbb{R}}^4$ using marked graph diagrams.

Geometric Topology · Mathematics 2019-09-17 Hiroshi Matsuda

Ng constructed an invariant of knots in ${\mathbb{R}}^3$, a combinatorial knot contact homology. Extending his study, we construct an invariant of surface-knots in ${\mathbb{R}}^4$ using diagrams in ${\mathbb{R}}^3$.

Geometric Topology · Mathematics 2019-09-17 Hiroshi Matsuda

For a knot K in S^3, let T(K) be the characteristic toric sub-orbifold of the orbifold (S^3,K) as defined by Bonahon and Siebenmann. If K has unknotting number one, we show that an unknotting arc for K can always be found which is disjoint…

Geometric Topology · Mathematics 2009-06-30 Cameron McA Gordon , John Luecke

We show that if a positive integral surgery on a knot K inside a homology sphere X with Seifert genus g(K) results in an induced knot K_n in X_n(K)=Y which has simple Floer homology, we should have n>=2g(K). Moreover, if X is the standard…

Geometric Topology · Mathematics 2010-03-19 Eaman Eftekhary

We discuss a concordance invariant constructed from Heegaard Floer homology "correction terms" and +/- 1 surgeries on knots in the three-sphere.

Geometric Topology · Mathematics 2010-07-13 Thomas D. Peters

The Upsilon invariant of a knot is a concordance invariant derived from knot Floer homology theory. It is a piecewise linear continuous function defined on the interval $[0,2]$. Borodzik and Hedden gave a question asking for which knots the…

Geometric Topology · Mathematics 2024-03-21 Keisuke Himeno

In a previous work, we defined an unoriented skein exact triangle in unoriented link Floer homology. In this paper, we iterate a modified version of this exact triangle and obtain a spectral sequence from various versions of Khovanov…

Geometric Topology · Mathematics 2025-05-06 Gheehyun Nahm

Using the knot Floer homology filtration, we define invariants associated to a knot in a three-manifold possessing non-vanishing Floer co(homology) classes. In the case of the Ozsvath-Szabo contact invariant we obtain an invariant of knots…

Geometric Topology · Mathematics 2007-08-06 Matthew Hedden