Study cohomology groups of specific Alexander f-quandles over finite fields.
problem Determining cohomology groups for a specific class of Alexander f-quandles.
method Analyzing the cohomology groups of Alexander f-quandles of the form Fq[T,S]/(T−ω,S−β). result Computed the second, third, and fourth cohomology groups.
Study of twisted Alexander matrices for certain quandles and their invariants.
problem Investigate f-twisted Alexander matrices for quandles associated with Alexander pairs. method Define and analyze f-twisted Alexander matrices of certain quandles, relate to Carter-Saito-Satoh's invariant, and discuss connections to quandle homology groups. result 0-th elementary ideal of f-twisted Alexander matrix can be described using Carter-Saito-Satoh's invariant. Establishes connection between Alexander polynomials and triangulations.
problem Alexander polynomials and their variants for knots.
method Introduces twisted Neumann--Zagier matrices for ideal triangulations.
result Formulas for Alexander polynomial and its variants.
Researchers extend Alexander polynomial to knotoids and linkoids.
problem Defining and studying Alexander polynomial extensions for knotoids and linkoids.
method Developed and proved conjecture on mock Alexander polynomial for knotoids and linkoids.
result Proved conjecture on mock Alexander polynomial for knotoids and linkoids.
Study Alexander matrices for link quandles and their relation to knot invariants.
problem Understanding Alexander matrices for link quandles and their applications to knot invariants.
method Investigate f-twisted Alexander matrices and their connection to quandle cocycle invariants. result Show that f-twisted Alexander invariants of knot quandles are stronger than those of knot groups. Study Alexander polynomials of ribbon and virtual knots using ribbon's intrinsic singularity.
problem Determining Alexander polynomials for ribbon and virtual knots.
method Using ribbon's intrinsic singularity information, defining half Alexander polynomial, and developing simplified formulas.
result New formulas for Alexander polynomials of general knots and virtual knots in terms of Gauss diagrams.
Paper discusses groups where twisted Alexander polynomials vanish.
problem Understanding groups with vanishing twisted Alexander polynomials.
method Introduced and studied twisted Alexander vanishing groups, constructed knots, and analyzed representations.
result Every faithful irreducible representation of a TAV group causes the twisted Alexander polynomial to be zero.
New knot invariant detects unknots.
problem Detecting unknots in knot theory.
method Introduced Alexander-Beck module as a refined Alexander module.
result Alexander-Beck module detects the unknot.
Alexander polynomials of links relate under homotopy ribbon concordance.
problem Understanding relationships between Alexander polynomials of links.
method Demonstrated through homotopy ribbon concordance.
result Alexander polynomial of L divides Alexander polynomial of J.
By considering a (not necessarily locally-flat) PL knot as the singular locus of a PL stratified pseudomanifold, we can use intersection homology theory to define intersection Alexander polynomials, a generalization of the classical Alexander polynomial invariants for smooth or PL locally-flat knots. We show that the i…
Efficient method for computing twisted Alexander polynomials of Montesinos links.
problem Computing twisted Alexander polynomials for Montesinos links efficiently.
method Developed an efficient method to compute the twisted Alexander polynomial for Montesinos links using any linear representation.
result Formulas for multi-variable Alexander polynomials can be easily derived.
The paper studies twisted Alexander polynomials for knot groups in various extensions.
problem Understanding twisted Alexander polynomials in knot groups for different extensions.
method Developed mod p formula for twisted Alexander polynomials and studied central extensions.
result Established formulas for twisted Alexander polynomials in knot groups for various extensions.
Study calculates twisted Alexander polynomials for Montesinos knots.
problem Tackles the calculation of twisted Alexander polynomials for Montesinos knots.
method Uses SL2(C)-representations to calculate leading coefficients and degrees of the polynomials. result Obtains non-monic twisted Alexander polynomials for some nonfibered knots.
Formula for Alexander polynomial of links with twists.
problem Computing Alexander polynomial of links with twists.
method Using vector space representation of Uq(gl(1∣1)). result Alexander polynomials stabilize after adding enough twists.
Study on a knot invariant's vanishing order.
problem Understanding the vanishing order of twisted Alexander polynomials.
method Defined and explored properties of the twisted Alexander vanishing order.
result Listed twisted Alexander vanishing groups of order less than 201.
We define twisted Alexander polynomials of a complex hypersurface with arbitrary singularities. These generalize the classical Alexander polynomials of high dimensional hypersurfaces and the twisted Alexander polynomial of plane curves. We recover the classical torsionness and divisibility results, which say that, unde…
A simplified proof of the Alexander-Conway polynomial exists.
problem Existence of the Alexander-Conway polynomial for links in 3D space.
method Presented an accurate detailed exposition of the proof.
result Existence of the Alexander-Conway polynomial proved.
A new quandle from link modules helps identify link properties.
problem Identifying link properties from their modules.
method Defining quandle operations on multivariate Alexander modules.
result The fundamental multivariate Alexander quandle determines the link module sequence.
It follows from earlier work of Silver-Williams and the authors that twisted Alexander polynomials detect the unknot and the Hopf link. We now show that twisted Alexander polynomials also detect the trefoil and the figure-8 knot, that twisted Alexander polynomials detect whether a link is split and that twisted Alexand…
The Alexander polynomial of a knot has been generalized in three different ways to give twisted invariants. The resulting invariants are usually referred to as twisted Alexander polynomials, higher-order Alexander polynomials and L2-Alexander invariants of knots. We quickly recall the definitions and we summarize an…
New Alexander polynomial for singular knots improves upon existing methods.
problem Defining a polynomial invariant for singular knots.
method Introducing a perturbed Alexander polynomial.
result The new polynomial agrees with previous definitions for long knots.
New Alexander invariants for knot groups computed using K1-groups.
problem Computing Alexander invariants for knot groups.
method Introducing K1-classes and comparing them with other Alexander polynomials. result Non-triviality of computed K1-classes for some knots. In this paper, we study the colorability of link diagrams by the Alexander quandles. We show that if the reduced Alexander polynomial ΔL(t) is vanishing, then L admits a non-trivial coloring by any non-trivial Alexander quandle Q, and that if ΔL(t)=1, then L admits only the trivial coloring by any Alexa…
The paper extends Alexander invariant and medial quandle equivalence to links.
problem Understanding stronger invariants for links than Alexander modules.
method Extending Joyce's observation to multiple medial quandles and reduced Alexander modules.
result Medial quandles provide stronger invariants than reduced Alexander modules for links.
New methods compute Alexander polynomials for complex knots.
problem Efficiently computing higher order Alexander polynomials for complex knots.
method Developed new algorithms to compute the Smith normal form of Alexander matrices.
result Computed Alexander polynomials for knots up to 100 crossings.
Paper computes Alexander polynomials for arborescent links.
problem Explicit formulas for Alexander polynomials are hard to compute for most link families.
method Efficient method for arborescent links, using recursive polynomials.
result Explicit closed formulas for pretzel links derived.
Given a virtual knot K, we construct a group VGK called the virtual knot group, and we use the elementary ideals of VGK to define invariants of K called the virtual Alexander invariants. For instance, associated to the k=0 ideal is a polynomial HK(s,t,q) in three variables which we call the virtual Alexa…
The paper extends Alexander and Markov theories to generalized knot theories.
problem Defining Alexander and Markov theories for generalized knot theories.
method Extending existing theories to new knot types.
result Alexander and Markov theories can be applied to generalized knot theories.
Study of Alexander modules for hyperplane arrangements, distinguishing complements.
problem Distinguishing homotopy equivalent but non-homeomorphic hyperplane arrangement complements.
method Analysis of twisted Alexander modules and polynomials.
result Distinguish non-homeomorphic homotopy equivalent arrangement complements.
Study on higher dimensional Alexander polynomials for metabelian representations of knots.
problem Analyzing the asymptotic behavior of Alexander polynomials for metabelian representations of knots.
method Investigating the leading coefficients of the asymptotics of twisted Alexander polynomials for SL(n, C)-representations induced from irreducible metabelian SL(2, C)-representations.
result Concrete computations for all genus one two-bridge knots presented, including limits of leading coefficients in the asymptotics of twisted Alexander polynomials.
Alexander quandles can be embedded into groups.
problem Embedding Alexander quandles into groups.
method For any twisted conjugate quandle, find a group such that the quandle is embedded into the conjugation quandle of the group.
result Alexander quandles can be embedded into groups.
Explicit formulas for pretzel knots' Alexander polynomials.
problem Alexander polynomial of pretzel knots
method Provided explicit formulas
result Characterization of pretzel knots with trivial Alexander polynomial
Murasugi discovered two criteria that must be satisfied by the Alexander polynomial of a periodic knot. We generalize these to the case of twisted Alexander polynomials. Examples demonstrate the application of these new criteria, including to knots with trivial Alexander polynomial, such as the two polynomial 1 knots w…
Homology handles with trivial Alexander polynomial bound a 3D sphere.
problem Understanding when homology handles bound 3D spheres.
method Using Freedman and Quinn's result for Z-homology 3-spheres. result A distinguished homology handle with trivial Alexander polynomial bounds a homology S1imesD3. Study Alexander polynomials of links in 3-torus.
problem Investigate Alexander polynomials of links in 3-torus.
method Diagrammatic approach, Reidemeister moves, fundamental group, homology group, Alexander polynomials, twisted Alexander polynomials.
result Computed Alexander and twisted Alexander polynomials of links in 3-torus.
Alexander quandles fail to distinguish certain links, thus not detecting causality.
problem Detecting causality in spacetimes using link polynomials.
method Examined Alexander quandles' ability to distinguish specific links.
result Alexander quandles cannot distinguish the connected sum of two Hopf links and Allen-Swenberg Links.
The study eliminates infinite families of knots with nontrivial Alexander polynomials and improves unknotting number data.
problem Identifying knots with nontrivial Alexander polynomials and improving knot classification.
method Elimination of infinite families of knots and use of determinants to improve unknotting number data.
result Elimination of infinite families of knots with nontrivial Alexander polynomials and improvement of unknotting number data.
New condition for Alexander polynomial factorization in 4D knots.
problem Alexander polynomial factorization for 2-knots in S4. method Alternative notion of ribbon 2-knots to prove factorization condition.
result Topological condition for factorization of Alexander polynomial.
Alexander polynomial equals spanning tree count at t=1.
problem Alexander polynomial for spatial graphs.
method Combinatorial constructions generalized to weighted graphs.
result Value of Alexander polynomial at t=1 equals weighted spanning tree count.
Alexander invariant created for doodles, vanishes on unlinked doodles.
problem Creating an Alexander type invariant for doodles.
method Deformation of Tits representation and Chebyshev polynomials of second kind.
result Invariant vanishes on unlinked doodles with more than one component.
Formula for twisted Alexander polynomials of torus links.
problem Computing twisted Alexander polynomials for torus links.
method Explicit formula derivation and character variety analysis.
result Locally constant function on character variety.
Alexander's conjecture extended to infinite simplicial complexes.
problem Alexander's conjecture for infinite simplicial complexes.
method Generalization of recent result for finite simplicial complexes.
result Alexander's conjecture holds for infinite simplicial complexes.
We introduce a new algebraic topological technique to detect non-fibred knots in the three sphere using the twisted Alexander invariants. As an application, we show that for any Seifert matrix of a knot with a nontrivial Alexander polynomial, there exist infinitely many non-fibered knots with the given Seifert matrix. …
Corrects a paper on Alexander modules and answers a related question.
problem Peripheral elements in reduced Alexander modules
method Analyzes and corrects a paper on Alexander modules
result Answers a question and corrects a minor error in the original paper
Cochran defined the nth-order integral Alexander module of a knot in the three sphere as the first homology group of the knot's (n+1)th-iterated abelian cover. The case n=0 gives the classical Alexander module (and polynomial). After a localization, one can get a finitely presented module over a principal ideal domain,…
Study of knot group completions links Alexander polynomials.
problem Determining knot equivalence via group completions.
method Analyzing completed group rings and Alexander modules.
result Isomorphic knot group completions imply identical Alexander polynomials.
J. Davis showed that the topological concordance class of a link in the 3-sphere is uniquely determined by its Alexander polynomial for 2-component links with Alexander polynomial one. A similar result for knots with Alexander polynomial one was shown earlier by M. Freedman. We prove that these two cases are the only e…
We observe the twisted Alexander polynomial for metabelian representations of knot groups into SL(2,C) and study relations to the characterizations of metabelian representations in the character varieties. We give a factorization of the twisted Alexander polynomial for irreducible metabelian representations with the ad…