English
Related papers

Related papers: The Structure of Biquandle Brackets

200 papers

We describe a way of representing finite biquandles with n elements as 2n x 2n block matrices. Any finite biquandle defines an invariant of virtual knots through counting homomorphisms. The counting invariants of non-quandle biquandles can…

Geometric Topology · Mathematics 2007-05-23 Sam Nelson , John Vo

A group-theoretical method, via Wada's representations, is presented to distinguish Kishino's virtual knot from the unknot. Biquandles are constructed for any group using Wada's braid group representations. Cocycle invariants for these…

Geometric Topology · Mathematics 2007-05-23 J. Scott Carter , Mohamed Elhamdadi , Masahico Saito , Daniel S. Silver , Susan G. Williams

We introduce quiver representation-valued invariants of oriented virtual knots and links associated to a choice of finite virtual biquandle, abelian group, set of virtual Boltzmann weights, commutative unital ring and set of virtual…

Geometric Topology · Mathematics 2025-11-18 Alexander Bishop , Jose Ceniceros , Sam Nelson

A birack is an algebraic structure with axioms encoding the blackboard-framed Reidemeister moves, incorporating quandles, racks, strong biquandles and semiquandles as special cases. In this paper we extend the counting invariant for finite…

Geometric Topology · Mathematics 2010-12-23 Sam Nelson

In this paper, we discuss the (co)homology theory of biquandles, derived biquandle cocycle invariants for oriented surface-links using broken surface diagrams and how to compute the biquandle cocycle invariants from marked graph diagrams.…

Geometric Topology · Mathematics 2018-03-09 Seiichi Kamada , Akio Kawauchi , Jieon Kim , Sang Youl Lee

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

In this paper, we build on the biquasiles and dual graph diagrams introduced in arXiv:1610.06969. We introduce \textit{biquasile Boltzmann weights} that enhance the previous knot coloring invariant defined in terms of finite biquasiles and…

Geometric Topology · Mathematics 2018-09-25 WonHyuk Choi , Deanna Needell , Sam Nelson

This article introduces a natural extension of colouring numbers of knots, called colouring polynomials, and studies their relationship to Yang-Baxter invariants and quandle 2-cocycle invariants. For a knot K in the 3-sphere let \pi_K be…

Geometric Topology · Mathematics 2007-11-20 Michael Eisermann

We introduce \textit{dual graph diagrams} representing oriented knots and links. We use these combinatorial structures to define corresponding algebraic structures we call \textit{biquasiles} whose axioms are motivated by dual graph…

Geometric Topology · Mathematics 2017-09-05 Deanna Needell , Sam Nelson

This paper is a memory of the work and influence of Vaughan Jones. It is an exposition of the remarkable breakthroughs in knot theory and low dimensional topology that were catalyzed by his work. The paper recalls the inception of the Jones…

Geometric Topology · Mathematics 2022-09-26 Louis H Kauffman

Given a biquandle $(X, S)$, a function $\tau$ with certain compatibility and a pair of {\em non commutative cocyles} $f,h:X \times X\to G$ with values in a non necessarily commutative group $G$, we give an invariant for singular knots /…

Geometric Topology · Mathematics 2019-10-10 Marco Farinati , Juliana García Galofre

We investigate connections between biquandle colorings, quiver enhancements, and several notions of the bridge numbers $b_i(K)$ for virtual links, where $i=1,2$. We show that for any positive integers $m \leq n$, there exists a virtual link…

Geometric Topology · Mathematics 2025-04-15 Tirasan Khandhawit , Puttipong Pongtanapaisan , Brandon Wang

We introduce two kinds of structures, called v-structures and t-structures, on biquandles. These structures are used for colorings of diagrams of virtual links and twisted links such that the numbers of colorings are invariants. Given a…

Geometric Topology · Mathematics 2015-12-29 Naoko Kamada , Seiichi Kamada

We define biquandle structures on a given quandle, and show that any biquandle is given by some biquandle structure on its underlying quandle. By determining when two biquandle structures yield isomorphic biquandles, we obtain a…

Group Theory · Mathematics 2020-08-10 Eva Horvat

In this short survey we review recent results dealing with algebraic structures (quandles, psyquandles, and singquandles) related to singular knot theory. We first explore the singquandles counting invariant and then consider several recent…

Geometric Topology · Mathematics 2021-03-10 Jose Ceniceros , Indu R. Churchill , Mohamed Elhamdadi , Mustafa Hajij

Biracks are algebraic structures related to knots and links. We define a new enhancement of the birack counting invariant for oriented classical and virtual knots and links via algebraic structures called birack dynamical cocycles. The new…

Geometric Topology · Mathematics 2012-05-22 Sam Nelson , Emily Watterberg

A method of computing a basis for the second Yang-Baxter cohomology of a finite biquandle with coefficients in Q and Z_p from a matrix presentation of the finite biquandle is described. We also describe a method for computing the…

Geometric Topology · Mathematics 2007-10-30 Conrad Creel , Sam Nelson

We generalize the notion of biquandles to psyquandles and use these to define invariants of oriented singular links and pseudolinks. In addition to psyquandle counting invariants, we introduce Alexander psyquandles and corresponding…

Geometric Topology · Mathematics 2017-10-25 Sam Nelson , Natsumi Oyamaguchi , Radmila Sazdanovic

We introduce the notion of a hierarchical quandle, which is a generalisation of diquandles and multi-quandles. Using hierarchical quandle colourings, we construct a cocycle invariants for links coloured by quandles.

Geometric Topology · Mathematics 2023-11-08 Philipp Korablev

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