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Related papers: Cocycle Invariants and Oriented Singular Knots

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The homology and cohomology of quandles and racks are used in knot theory: given a finite quandle and a cocycle, we can construct a knot invariant. This is a quick introductory survey to the invariants of knots derived from quandles and…

Geometric Topology · Mathematics 2007-05-23 Seiichi Kamada

We define ambient isotopy invariants of oriented knots and links using the counting invariants of framed links defined by finite racks. These invariants reduce to the usual quandle counting invariant when the rack in question is a quandle.…

Geometric Topology · Mathematics 2013-07-30 Sam Nelson

We enhance the psyquandle counting invariant for singular knots and pseudoknots using quivers analogously to quandle coloring quivers. This enables us to extend the in-degree polynomial invariants from quandle coloring quiver theory to the…

Geometric Topology · Mathematics 2021-07-14 Jose Ceniceros , Anthony Christiana , Sam Nelson

This paper studies an algebraic invariant of virtual knots called the biquandle. The biquandle generalizes the fundamental group and the quandle of virtual knots. The approach taken in this paper to the biquandle emphasizes understanding…

Geometric Topology · Mathematics 2007-05-23 David Hrencecin , Louis H. Kauffman

This paper contains the first knot polynomials which can distinguish the orientations of classical knots and which make no excplicit use of the knot group. But they make extensive use of the meridian and of the longitude in a geometric way.…

Geometric Topology · Mathematics 2023-01-18 Thomas Fiedler

We introduce a new class of quantum enhancements we call biquandle brackets, which are customized skein invariants for biquandle colored links.Quantum enhancements of biquandle counting invariants form a class of knot and link invariants…

Geometric Topology · Mathematics 2017-02-17 Sam Nelson , Michael E. Orrison , Veronica Rivera

We construct two complete invariants of oriented classical knots in space. The value of each invariant on any knot is a set, infinite for the first invariant and finite for the second. The finite set is computed algorithmically from any…

Geometric Topology · Mathematics 2023-06-02 Dimitrios Kodokostas

Yang-Baxter operators (YBOs) have been employed to construct quantum knot invariants. More recently, cohomology theories for YBOs have been independently developed, drawing inspiration from analogous theories for quandles and other discrete…

Geometric Topology · Mathematics 2025-11-17 Masahico Saito , Emanuele Zappala

We introduce new skein invariants of links based on a procedure where we first apply the skein relation only to crossings of distinct components, so as to produce collections of unlinked knots. We then evaluate the resulting knots using a…

Geometric Topology · Mathematics 2019-04-04 Louis H. Kauffman , Sofia Lambropoulou

Quandle homology theory has been developed and cocycles have been used to define invariants of oriented classical or surface links. We introduce a shifting chain map $\sigma$ on each quandle chain complex that lowers the dimensions by one.…

Geometric Topology · Mathematics 2021-03-22 Yu Hashimoto , Kokoro Tanaka

The aim of this paper is to define certain algebraic structures coming from generalized Reidemeister moves of singular knot theory. We give examples, show that the set of colorings by these algebraic structures is an invariant of singular…

Geometric Topology · Mathematics 2018-06-21 Indu R. U. Churchill , M. Elhamdadi , M. Hajij , Sam Nelson

Quandle cocycle invariants form a powerful and well developed tool in knot theory. This paper treats their variations - namely, positive and twisted quandle cocycle invariants, and shadow invariants. We interpret the former as particular…

Geometric Topology · Mathematics 2014-10-07 Seiichi Kamada , Victoria Lebed , Kokoro Tanaka

Non-classical virtual knots may have non-isomorphic upper and lower quandles. We exploit this property to define the quandle difference invariant, which can detect non-classicality by comparing the numbers of homomorphisms into a finite…

Geometric Topology · Mathematics 2007-05-23 Natasha Harrell , Sam Nelson

We define relative versions of the classical invariants of Legendrian and transverse knots in contact 3-manifolds for knots that are homologous to a fixed reference knot. We show these invariants are well-defined and give some basic…

Symplectic Geometry · Mathematics 2009-09-25 Georgi D. Gospodinov

This paper studies the chirality of knotoids using shadow quandle colorings and the shadow quandle cocycle invariant. The shadow coloring number and the shadow quandle cocycle invariant is shown to distinguish infinitely many knotoids from…

Geometric Topology · Mathematics 2022-07-08 Nicholas Cazet

We introduce and investigate oriented dichromatic singular links. We also introduce oriented disingquandles and use them to define counting invariants for oriented dichromatic singular links. We provide some examples to show that these…

Geometric Topology · Mathematics 2024-01-12 Mohd Ibrahim Sheikh , Mohamed Elhamdadi , Danish Ali

In this paper we introduce a new invariant of virtual knots and links that is non-trivial for infinitely many virtuals, but is trivial on classical knots and links. The invariant is initially be expressed in terms of a relative of the…

Geometric Topology · Mathematics 2007-05-23 Louis H. Kauffman

In this paper we study oriented quantum coalgebras which are structures closely related to oriented quantum algebras. We study the relationship between oriented quantum coalgebras and oriented quantum algebras and the relationship between…

Quantum Algebra · Mathematics 2010-04-09 Louis Kauffman , David E. Radford

Finite-order invariants of knots in arbitrary 3-manifolds (including non-orientable ones) are constructed and studied by methods of the topology of discriminant sets. Obstructions to the integrability of admissible weight systems to…

Geometric Topology · Mathematics 2016-09-07 Victor A. Vassiliev

We define new invariants of knots by means of quandle colorings and longitudinal information. These invariants can be applied to a tangle embedding problem and recognizing non-classical virtual knots.

Geometric Topology · Mathematics 2019-10-29 Maciej Niebrzydowski