English
Related papers

Related papers: Hierarchical quandles

200 papers

We construct a virtual quandle for links in lens spaces $L(p,q)$, with $q=1$. This invariant has two valuable advantages over an ordinary fundamental quandle for links in lens spaces: the virtual quandle is an essential invariant and the…

Algebraic Topology · Mathematics 2017-02-21 A. Cattabriga , T. Nasybullov

In this paper, a theory of quandle rings is proposed for quandles analogous to the classical theory of group rings for groups, and interconnections between quandles and associated quandle rings are explored.

Group Theory · Mathematics 2021-07-22 Valeriy G. Bardakov , Inder Bir Singh Passi , Mahender Singh

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

A quandle coloring quiver is a quiver structure, introduced by Karina Cho and Sam Nelson, which is defined on the set of quandle colorings of an oriented knot or link by a finite quandle. We study quandle coloring quivers of (p, 2)-torus…

Geometric Topology · Mathematics 2022-09-13 Jagdeep Basi , Carmen Caprau

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

Biquandle brackets are a type of quantum enhancement of the biquandle counting invariant for oriented knots and links, defined by a set of skein relations with coefficients which are functions of biquandle colors at a crossing. In this…

Geometric Topology · Mathematics 2019-09-04 Neslihan Gügümcü , Sam Nelson , Natsumi Oyamaguchi

We introduce new families of quandles that serve as invariants for classifying closed orientable surfaces. These families generalize the classical Dehn quandle and are defined, respectively, on isotopy classes of unoriented closed curves…

Geometric Topology · Mathematics 2026-02-20 Pankaj Kapari , Deepanshi Saraf , Mahender Singh

The axioms of a quandle imply that the columns of its Cayley table are permutations. This paper studies quandles with exactly one non-trivially permuted column. Their automorphism groups, quandle polynomials, (symmetric) cohomology groups,…

Quantum Algebra · Mathematics 2024-01-31 Nicholas Cazet

The state-sum invariants for knots and knotted surfaces defined from quandle cocycles are described using the Kronecker product between cycles represented by colored knot diagrams and a cocycle of a finite quandle used to color the diagram.…

Geometric Topology · Mathematics 2007-05-23 J. Scott Carter , Seiichi Kamada , Masahico Saito

We introduce and investigate dichromatic singular links. We also construct G-Family of singquandles and use them to define counting invariants for unoriented dichromatic singular links. We provide some examples to show that these invariants…

Geometric Topology · Mathematics 2023-01-11 Mohd Ibrahim Sheikh , Mohamed Elhamdadi , Danish Ali

We generalise the finite biquandle colouring invariant to a polynomial invariant based on labelling a knot diagram with a finite birack that reduces to the biquandle colouring invariant in that case. The polynomial is an invariant of a…

Geometric Topology · Mathematics 2025-03-12 Andrew Bartholomew , Roger Fenn , Louis Kauffman

We introduce a new algebraic structure called \textit{local biquandles} and show how colorings of oriented classical link diagrams and of broken surface diagrams are related to tribracket colorings. We define a (co)homology theory for local…

Geometric Topology · Mathematics 2019-02-19 Sam Nelson , Kanako Oshiro , Natsumi Oyamaguchi

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

We introduce an infinite family of quantum enhancements of the biquandle counting invariant we call biquandle virtual brackets. Defined in terms of skein invariants of biquandle colored oriented knot and link diagrams with values in a…

Geometric Topology · Mathematics 2019-08-28 Sam Nelson , Kanako Oshiro , Ayaka Shimizu , Yoshiro Yaguchi

We introduce two notions of quandle polynomials for G-families of quandles: the quandle polynomial of the associated quandle and a G-family polynomial with coefficients in the group ring of G. As an application we define image subquandle…

Geometric Topology · Mathematics 2021-11-12 Sam Nelson , Madeline Brown

A quandle equipped with a good involution is referred to as symmetric. It is known that the cohomology of symmetric quandles gives rise to strong cocycle invariants for classical and surface links, even when they are not necessarily…

Quantum Algebra · Mathematics 2025-10-17 Biswadeep Karmakar , Deepanshi Saraf , Mahender Singh

We enhance the quandle coloring quiver invariant of oriented knots and links with quandle modules. This results in a two-variable polynomial invariant with specializes to the previous quandle module polynomial invariant as well as to the…

Geometric Topology · Mathematics 2020-11-12 Karma Istanbouli , Sam Nelson

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

This paper is devoted to qualgebras and squandles, which are quandles enriched with a compatible binary/unary operation. Algebraically, they are modeled after groups with conjugation and multiplication/squaring operations. Topologically,…

Algebraic Topology · Mathematics 2014-02-27 Victoria Lebed

It is known that the number of biquandle colorings of a long virtual knot diagram, with a fixed color of the initial arc, is a knot invariant. In this paper we describe a more subtle invariant: a family of biquandle endomorphisms obtained…

Geometric Topology · Mathematics 2019-10-29 Maciej Niebrzydowski