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Related papers: $L^2$-Alexander invariant for knots

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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

Given a virtual knot $K$, we construct a group $VG_K$ called the virtual knot group, and we use the elementary ideals of $VG_K$ to define invariants of $K$ called the virtual Alexander invariants. For instance, associated to the $k=0$ ideal…

Geometric Topology · Mathematics 2015-05-07 Hans U. Boden , Emily Dies , Anne Isabel Gaudreau , Adam Gerlings , Eric Harper , Andrew J. Nicas

The central question of knot theory is that of distinguishing links up to isotopy. The first polynomial invariant of links devised to help answer this question was the Alexander polynomial (1928). Almost a century after its introduction, it…

Geometric Topology · Mathematics 2023-10-27 Elena S. Hafner , Karola Mészáros , Alexander Vidinas

In our previous work, we introduced the notion of the twisted Alexander vanishing order of knots, defined as the order of the smallest finite group for which the corresponding twisted Alexander polynomial vanishes. In this paper, we explore…

Geometric Topology · Mathematics 2025-10-30 Katsumi Ishikawa , Takayuki Morifuji , Masaaki Suzuki

The classical abelian invariants of a knot are the Alexander module, which is the first homology group of the the unique infinite cyclic covering space of S^3-K, considered as a module over the (commutative) Laurent polynomial ring, and the…

Geometric Topology · Mathematics 2014-10-01 Tim D. Cochran

We introduce two new families of polynomial invariants of oriented classical and virtual knots and links defined as decategorfications of the quandle coloring quiver. We provide examples to illustrate the computation of the invariants, show…

Geometric Topology · Mathematics 2025-08-18 Anusha Kabra , Sam Nelson

The perturbed Alexander invariant $\rho_1$, defined by Bar-Natan and van der Veen, is a powerful, easily computable polynomial knot invariant with deep connections to the Alexander and colored Jones polynomials. We study the behavior of…

Geometric Topology · Mathematics 2025-11-07 Joe Boninger

We establish a connection between the Alexander polynomial of a knot and its twisted and $L^2$-versions with the triangulations that appear in 3-dimensional hyperbolic geometry. Specifically, we introduce twisted Neumann--Zagier matrices of…

Geometric Topology · Mathematics 2026-03-12 Stavros Garoufalidis , Seokbeom Yoon

We construct two knot invariants. The first knot invariant is a sum constructed using linking numbers. The second is an invariant of flat knots and is a formal sum of flat knots obtained by smoothing pairs of crossings. This invariant can…

Geometric Topology · Mathematics 2011-09-15 H. A. Dye

In 1928, Alexander defined a sequence of knot polynomials, D_i(K). The first, D_1(K), is the classical Alexander polynomial. These are easily defined in terms of the homology of the infinite cyclic cover of the knot. In theory they can be…

Geometric Topology · Mathematics 2025-11-11 Charles Livingston

We find that Alexander polynomial of a ribbon knot in $ \mathbb{Z}HS^3 $ is determined by the intrinsic singularity information of its ribbon, and give a formula to calculate Alexander polynomial of a ribbon knot by that. We define half…

Geometric Topology · Mathematics 2026-05-21 Sheng Bai

We define a group-valued invariant of virtual knots and relate it to various other group-valued invariants of virtual knots, including the extended group of Silver-Williams and the quandle group of Manturov and Bardakov-Bellingeri. A…

Geometric Topology · Mathematics 2017-07-14 Hans U. Boden , Robin Gaudreau , Eric Harper , Andrew J. Nicas , Lindsay White

Twisted torus knots are a generalization of torus knots, obtained by introducing additional full twists to adjacent strands of the torus knots. In this article, we present an explicit formula for the Alexander polynomial of twisted torus…

Geometric Topology · Mathematics 2025-09-10 Adnan , Kyungbae Park

The twisted Alexander polynomial of a knot is defined associated to a linear representation of the knot group. If there exists a surjective homomorphism of a knot group onto a finite group, then we obtain a representation of the knot group…

Geometric Topology · Mathematics 2024-01-08 Takayuki Morifuji , Masaaki Suzuki

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

The fundamental problem of knot theory is to know whether two knots are equivalent or not. As a tool to prove that two knots are different, mathematicians have developed various invariants. Knots invariants are just functions that can be…

Geometric Topology · Mathematics 2018-11-26 Leandro Vendramin

In this paper we describe what should perhaps be called a `type-2' Vassiliev invariant of knots S^2 -> S^4. We give a formula for an invariant of 2-knots, taking values in Z_2 that can be computed in terms of the double-point diagram of the…

Geometric Topology · Mathematics 2026-01-13 Ryan Budney

We discuss different invariants of knots and links that depend on a primitive root of unity. We clarify the definitions of existing invariants with the Reshetikhin-Turaev method, present the generalization of ADO invariants to…

High Energy Physics - Theory · Physics 2022-08-10 Liudmila Bishler

We publish a table of primitive finite-type invariants of order less than or equal to six, for knots of ten or fewer crossings. We note certain mod-2 congruences, one of which leads to a chirality criterion in the Alexander polynomial. We…

Geometric Topology · Mathematics 2007-05-23 Ted Stanford

A polynomial is presented that models a topological knot in a unique manner. It distinguishes all types of knots including the orientation and has a group theory interpretation. The topologies may be labeled via a number, which upon a base…

General Physics · Physics 2007-05-23 Gordon Chalmers