New invariant measures complexity of 2-knots in 4D space.
problem Measuring complexity of 2-knots in 4D space.
method Introduced shadow-complexity based on Turaev shadows.
result Characterized 2-knots with shadow-complexity up to 1.
Algorithm computes knot Floer complex for knots of thickness one.
problem Computing knot Floer complexes for knots of thickness one.
method Developed and implemented an algorithm for knots of thickness one.
result Algorithm can compute full knot Floer complex for knots of thickness one.
Study algebraic obstructions to knot-like complex realizability.
problem Algebraic obstructions to knot-like complex realizability.
method Classification of local equivalence classes over F[U,V]. result Classification answers a question about knot-like complexes.
New complexity measure for shake-slice knots established.
problem Defining and measuring complexity for shake-slice knots.
method Using dualizable patterns and studying knot signatures.
result Existence of n-shake-slice knots with specified complexity. Gordian complex of knots was defined by Hirasawa and Uchida as the simplicial complex whose vertices are knot isotopy classes in S3. Later Horiuchi and Ohyama defined Gordian complex of virtual knots using v-move and forbidden moves. In this paper we discuss Gordian complex of knots by region crossing cha…
We construct families of trivial 2-knots Ki in R4 such that the maximal complexity of 2-knots in any isotopy connecting Ki with the standard unknot grows faster than a tower of exponentials of any fixed height of the complexity of Ki. Here we can either construct Ki as smooth embeddings and …
Study of knots and links in 2-complexes, defining linking numbers and polynomials.
problem Understanding knots and links in 2-dimensional complexes.
method Definition of linking numbers and Kauffman-type bracket polynomials for links in 2-complexes.
result Established relationships between 2-complexes and knots/links in 3-manifolds.
Proves volume conjecture for twist knots using complex analysis.
problem Volume conjecture for twist knots.
method Equivalence relation, complex analysis, analytic continuation, function of several complex variables.
result Proves volume conjecture for twist knots.
We show that the genus problem for alternating knots with n crossings has linear time complexity and is in Logspace(n). Almost all alternating knots of given genus possess additional combinatorial structure, we call them standard. We show that the genus problem for these knots belongs to TC0 circuit complexity c…
In "Width complexes for knots and 3-manifolds," Jennifer Schultens defines the width complex for a knot in order to understand the different positions a knot can occupy in the 3-sphere and the isotopies between these positions. She poses several questions about these width complexes; in particular, she asks whether the…
New method generates optical vortices in any knot shape.
problem Generating optical vortices in complex shapes beyond simple knots.
method Mathematical construction and experimental verification.
result Complex optical fields can form any knot shape.
The paper constructs exotic knotted surfaces and curves in 4-manifolds.
problem Understanding exotic knotted surfaces and curves in 4-manifolds.
method Local knotting and construction of surfaces and curves.
result First examples of exotically knotted complex curves and symplectic 2-spheres.
The paper classifies knot Floer complexes of low width, simplifying knot bases.
problem Classifying knot Floer complexes of low width.
method Using chain homotopy equivalence and local systems.
result All Montesinos knots admit a simplified basis.
Two Heegaard Floer knot complexes are called stably equivalent if an acyclic complex can be added to each complex to make them filtered chain homotopy equivalent. Hom showed that if two knots are concordant, then their knot complexes are stably equivalent. Invariants of stable equivalence include the concordance invari…
New method speeds up knot computations in 3D.
problem Computational complexity in knot theory.
method 3D representation of knots for faster computation.
result Savings in computational complexity for knot invariants.
The paper proves a linear diameter bound for hyperbolic knot complexes.
problem Understanding the diameter of Kakimizu complexes for hyperbolic knots.
method Defined a complex ISℓ(K) to study incompressible Seifert surfaces and proved its diameter has a linear upper bound. result The diameter of the Kakimizu complex for hyperbolic knots grows linearly with genus, confirming a conjecture.
Smooth knots in complex hyperbolic plane limit sets to chains or R-circles.
problem Characterizing limit sets of knots in complex hyperbolic geometry.
method Analyzing embeddings of knots as limit sets of discrete subgroups of PU(2, 1).
result Knots are either chains or R-circles as limit sets.
Automatic computation speeds up crosscap number calculation for alternating knots.
problem Computing crosscap numbers for alternating knots efficiently.
method Introduced an automatic computation with complexity O(E3). result Crosscap numbers of alternating knots can be computed in O(E3) time. Investigates ropelength of complex knots and links.
problem Establishing ropelength for knots and links beyond tested crossing numbers.
method Investigated torus knots up to 1023 crossings, satellite knots up to 42 crossings, and used a model of repeated Hopf links.
result Found power-law scaling in T(p,p+1) and derived formulae for predicting crossing-ropelength relationships.
Extends knot invariant to filtered grid complexes.
problem Knot invariants and grid complexes.
method Combining Ozsváth-Szabó-Stipsicz crossing-change maps with Alishahi-Eftekhary l(K) invariant.
result Combinatorial formulation of knot invariant.
Computer experiments reveal complex knots that don't simplify.
problem Understanding the dynamics of complex knots under self-repulsion.
method Computer simulations of knot theory, focusing on rational knots and tangles.
result Discovered hard unknots and complexified knots that do not reduce to simpler forms under self-repulsion.
This paper computes Kakimizu complexes for all 11 crossing prime alternating knots.
problem Computing Kakimizu complexes for prime, alternating knots with 11 crossings.
method Used known algorithms and Murasugi sums with sutured manifold theory.
result Explicitly described Kakimizu complexes for all 11 crossing prime alternating knots.
Proofs knot homology connected sums using grid complexes.
problem Proving Künneth formula for knot Floer homology of connected sums.
method Constructs a quasi-isomorphism of grid chain complexes.
result Functorial behavior of Legendrian and transverse invariants under connected sum.
The paper determines the structure of Kakimizu complexes for genus one hyperbolic knots.
problem Understanding the structure of Kakimizu complexes for genus one hyperbolic knots.
method Analyzing the simplicial complex of minimal genus Seifert surfaces in the exterior of the knots.
result The Kakimizu complex for genus one hyperbolic knots consists of a single d-simplex for d=0,4 and otherwise of at most two d-simplices which intersect in a common (d−1)-face. We show that the problem of recognizing that a knot diagram represents a specific torus knot, or any torus knot at all, is in the complexity class NP∩co-NP, assuming the generalized Riemann hypothesis. We also show that satellite knot detection is in NP under the same assumption, and t…
New Garside structures found for torus knot groups and related braid groups.
problem Finding Garside structures for torus knot groups and related braid groups.
method Introducing a new Garside monoid M(n,m) for (n,m)-torus knot groups and other braid groups. result New Garside structures for (n,m)-torus knot groups and related braid groups are constructed. Knots can be constructed and decomposed using Murasugi sums of Seifert surfaces.
problem Understanding the structure of knots through Murasugi sums.
method Using Murasugi sums to decompose and construct knots, showing the structure of a bi-directed complete graph.
result Any knot can be a Murasugi sum of any two knots, with bounds on minimal complexity.
Knots can be embedded into fractals like the Menger Sponge and Sierpinski Tetrahedron.
problem Embedding knots into fractals to compare complexity.
method Proved all knots can be embedded into Menger Sponge, and Pretzel knots into Sierpinski Tetrahedron. Compared iterations needed for given knots.
result Comparison of fractal complexity through knot embedding.
Sharp bounds for Kirby-Thompson invariants of knotted surfaces computed.
problem Computing sharp lower bounds for Kirby-Thompson invariants of knotted surfaces.
method Using dual curve complex distances to compute invariants.
result Exact values of KT-invariants computed for knotted surfaces with bridge number ≤ 6.
We modify an approach of Johnson to define the distance of a bridge splitting of a knot in a 3-manifold using the dual curve complex and pants complex of the bridge surface. This distance can be used to determine a complexity, which becomes constant after a sufficient number of stabilizations and perturbations, yieldin…
Yokota suggested an optimistic limit method of the Kashaev invariants of hyperbolic knots and showed it determines the complex volumes of the knots. His method is very effective and gives almost combinatorial method of calculating the complex volumes. However, to describe the triangulation of the knot complement, he re…
Study shows crossing numbers for algebraic knots can differ by arbitrarily large amounts.
problem Comparing two crossing number definitions for algebraic knots.
method Analyzed Hopf fibration and complex singularities to compare crossing numbers.
result Difference between crossing numbers can be arbitrarily large.
Formula for satellite operators using knot Floer homology.
problem Computing knot Floer homology for satellite knots.
method Using Heegaard Floer Dehn surgery formulas and formal knot Floer complexes.
result Formulas to compute knot Floer homology for satellite knots.
New method computes knot Floer homology for satellite knots.
problem Computing knot Floer homology for satellite knots.
method Using immersed Heegaard diagrams and bordered Floer homology.
result Computation of knot Floer homology for satellite knots streamlined.
New estimate of semimeander complexity for knots with more than 10 crossings.
problem Estimating the complexity of semimeander diagrams of knots.
method Proved a new upper bound on the number of crossings for semimeander diagrams of knots with more than 10 crossings.
result For knots with more than 10 crossings, semimeander diagrams have no more than 0.31⋅1.558cr(K) crossings. Formula calculates knot Floer complexes for specific cable knots.
problem Computing knot Floer complexes for (n,1)-cable knots. method Filtered mapping cone formula generalizing previous results.
result Existence of knots with arbitrary concordance homomorphisms values.
Verifies knot conjecture for 24-crossing knots.
problem Jones Unknot Conjecture for knots up to 24 crossings.
method Described method of verification with complexity analysis.
result Jones Unknot Conjecture verified for 24 crossings.
We prove that if two knots are concordant, their involutive knot Floer complexes satisfy a certain type of stable equivalence.
We define a new smooth concordance homomorphism based on the knot Floer complex and an associated concordance invariant, epsilon. As an application, we show that an infinite family of topologically slice knots are independent in the smooth concordance group.
New bounds found for complexity of spun knots.
problem Measuring complexity of spun knots.
method Using bridge trisections and distances in the pants complex.
result Bound the Kirby-Thompson invariant of spun knots.
We establish upper bounds for the complexity of Seifert fibered manifolds with nonempty boundary. In particular, we obtain potentially sharp bounds on the complexity of torus knot complements.
Tests using knot Floer homology detect prime knots with high accuracy.
problem Detecting prime knots efficiently.
method Knot Floer homology and polynomial irreducibility tests.
result Over 96% of non-hyperbolic prime knots up to 20 crossings are identified as prime.
The genus of knots is a one of the fundamental invariant and can be seen as a complexity of knots. In this paper, we give a lower bound of genus using Dehornoy floor, which is a measure of complexity of braids in terms of braid ordering.
We show that the Kakimizu complex of a knot may be locally infinite, answering a question of Przytycki--Schultens. We then prove that if a link L only has connected Seifert surfaces and has a locally infinite Kakimizu complex then L is a satellite of either a torus knot, a cable knot or a connected sum, with windin…
New subgroup found in knot homology concordance group.
problem Understanding the structure of knot homology concordance groups.
method Applying filtered mapping cone formula to L-space knots and using connected knot complex.
result Contains a Z∞ subgroup. New formula for dual knots using involutions.
problem Understanding dual knots and their transformations.
method Involutive analog of knot surgery formula.
result Computed local equivalence class for involutive dual knots.
Calculates knot X-torsion order using spectral sequences.
problem Calculating the X-torsion order of knots. method Using the reduced Bar-Natan--Lee--Turner spectral sequence.
result Example of X-torsion order 4. 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.