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Related papers: A Rasmussen invariant for links in $\mathbb{RP}^3$

200 papers

We put a new spin on Khovanov--Rozansky homology. That is, we equip $\Lambda^n$-colored $\mathfrak{sl}_{2n}$ Khovanov--Rozansky homology with an involution whose $\pm 1$-eigenspaces are link invariants. When $n=1,2,3$ (and assuming…

Quantum Algebra · Mathematics 2024-07-02 Elijah Bodish , Ben Elias , David E. V. Rose

We define an integer valued invariant for two-component links in S^3 by counting projective SU(2) representations of the link group having non-trivial second Stiefel-Whitney class. We show that our invariant is, up to sign, the linking…

Geometric Topology · Mathematics 2009-11-23 Eric Harper , Nikolai Saveliev

We generalize Ng's two-variable algebraic/combinatorial $0$-th framed knot contact homology for framed oriented knots in $S^3$ to knots in $S^1 \times S^2$, and prove that the resulting knot invariant is the same as the framed cord algebra…

Quantum Algebra · Mathematics 2016-07-01 Shawn X. Cui , Zhenghan Wang

A well-known conjecture of Rasmussen states that for any knot $K$ in $S^{3}$, the rank of the reduced Khovanov homology of $K$ is greater than or equal to the rank of the reduced knot Floer homology of $K$. This rank inequality is supposed…

Geometric Topology · Mathematics 2018-11-20 Nathan Dowlin

The purpose of this paper is to construct and study equivariant Khovanov homology - a version of Khovanov homology theory for periodic links. Since our construction works regardless of the characteristic of the coefficient ring it…

Geometric Topology · Mathematics 2020-01-28 Wojciech Politarczyk

Tied links and the tied braid monoid were introduced recently by the authors and used to define new invariants for classical links. Here, we give a version purely algebraic-combinatoric of tied links. With this new version we prove that the…

Geometric Topology · Mathematics 2021-01-28 Francesca Aicardi , Jesus Juyumaya

We give a fresh introduction to the Khovanov Homology theory for knots and links, with special emphasis on its extension to tangles, cobordisms and 2-knots. By staying within a world of topological pictures a little longer than in other…

Geometric Topology · Mathematics 2014-11-11 Dror Bar-Natan

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 prove a rank inequality on the instanton knot homology and the Khovanov homology of a link in $S^3$. The key step of the proof is to construct a spectral sequence relating Baldwin-Levine-Sarkar's pointed Khovanov homology to a singular…

Geometric Topology · Mathematics 2018-09-26 Yi Xie

Lawrence Roberts, extending the work of Ozsvath-Szabo, showed how to associate to a link, L, in the complement of a fixed unknot, B, in S^3, a spectral sequence from the Khovanov homology of a link in a thickened annulus to the knot Floer…

Geometric Topology · Mathematics 2013-03-25 J. Elisenda Grigsby , Stephan M. Wehrli

Ozsvath and Szabo show that there is a spectral sequence whose E^2 term is the reduced Khovanov homology of L, and which converges to the Heegaard Floer homology of the (orientation reversed) branched double cover of S^3 along L. We prove…

Geometric Topology · Mathematics 2009-11-23 John A. Baldwin

We construct analogs of Khovanov-Jacobsson classes and the Rasmussen invariant for links in the boundary of any smooth oriented 4-manifold. The main tools are skein lasagna modules based on equivariant and deformed versions of…

Geometric Topology · Mathematics 2026-03-06 Kim Morrison , Kevin Walker , Paul Wedrich

In this paper we present several counterexamples to Rasmussen's conjecture that the concordance invariant coming from Khovanov homology is equal to twice the invariant coming from Ozsv{\'a}th-Szab{\'o} Floer homology. The counterexamples…

Geometric Topology · Mathematics 2007-05-23 Matthew Hedden , Philip Ording

Knots and links in 3-manifolds are studied by applying intersection invariants to singular concordances. The resulting link invariants generalize the Arf invariant, the mod 2 Sato-Levine invariants, and Milnor's triple linking numbers.…

Geometric Topology · Mathematics 2016-01-20 Rob Schneiderman

We use Lee's work on the Khovanov homology to define a knot invariant s. We show that s(K) is a concordance invariant and that it provides a lower bound for the slice genus of K. As a corollary, we give a purely combinatorial proof of the…

Geometric Topology · Mathematics 2007-05-23 Jacob A. Rasmussen

Asaeda, Przytycki and Sikora defined a generalization of Khovanov homology for links in $I$-bundles over compact surfaces. We prove that for a link $L\subset (-1,1)\times T^2$, the Asaeda-Przytycki-Sikora homology of $L$ has rank $2$ with…

Geometric Topology · Mathematics 2020-05-27 Yi Xie , Boyu Zhang

We introduce an invariant of tangles in Khovanov homology by considering a natural inverse system of Khovanov homology groups. As application, we derive an invariant of strongly invertible knots; this invariant takes the form of a graded…

Geometric Topology · Mathematics 2017-04-07 Liam Watson

We use the divide-and-conquer and scanning algorithms for calculating Khovanov cohomology directly on the Lee- or Bar-Natan deformations of the Khovanov complex to give an alternative way to compute Rasmussen $s$-invariants of knots. By…

Geometric Topology · Mathematics 2018-11-16 Dirk Schuetz

We define a Rasmussen $s$-invariant over the coefficient ring of the integers, and show how it is related to the $s$-invariants defined over a field. A lower bound for the slice genus of a knot arising from it is obtained, and we give…

Geometric Topology · Mathematics 2022-02-02 Dirk Schuetz

For every positive integer $n$ we construct a bigraded homology theory for links, such that the corresponding invariant of the unknot is closely related to the U(n)-equivariant cohomology ring of $\mathbb{CP}^{n-1}$; our construction…

Quantum Algebra · Mathematics 2008-05-08 Daniel Krasner