English
Related papers

Related papers: Statistics on some classes of knot shadows

200 papers

We present a complete classification of spherical knotoids with up to six crossings and conjecture that our classification up to seven crossings is complete. Our work extends the tradition of knot tabulation to the setting of knotoids…

Geometric Topology · Mathematics 2026-03-09 Boštjan Gabrovšek , Paolo Cavicchioli

We have developed a reinforcement learning agent that often finds a minimal sequence of unknotting crossing changes for a knot diagram with up to 200 crossings, hence giving an upper bound on the unknotting number. We have used this to…

Many invariants of knots rely upon smoothing the knot at its crossings. To compute them, it is necessary to know how to count the number of connected components the knot diagram is broken into after the smoothing. In this paper, it is shown…

Geometric Topology · Mathematics 2013-04-01 Micah W. Chrisman

This note provides new closed forms evaluations of a few classes of exponential sums associated with elliptic curves and hyperelliptic curves.

Number Theory · Mathematics 2011-03-23 N. A. Carella

The notion of a braided chord diagram is introduced and studied. An equivalence relation is given which identifies all braidings of a fixed chord diagram. It is shown that finite-type invariants are stratified by braid index for knots which…

Geometric Topology · Mathematics 2007-05-23 Joan S. Birman , Rolland Trapp

An embedded graph is called $z$-knotted if it contains the unique zigzag (up to reversing). We consider $z$-knotted triangulations, i.e. $z$-knotted embedded graphs whose faces are triangles, and describe all cases when the connected sum of…

Combinatorics · Mathematics 2017-08-15 Mark Pankov , Adam Tyc

Classical knots in $\mathbb{R}^3$ can be represented by diagrams in the plane. These diagrams are formed by curves with a finite number of transverse crossings, where each crossing is decorated to indicate which strand of the knot passes…

Geometric Topology · Mathematics 2013-09-30 Allison Henrich , Rebecca Hoberg , Slavik Jablan , Lee Johnson , Elizabeth Minten , Ljiljana Radovic

Ascending numbers are determined for 64 knots with at most n=10 crossings. After proving the theorem about the signature of alternating knot families, we distinguished all families of knots obtained from generating alternating knots with at…

Geometric Topology · Mathematics 2011-07-13 Slavik Jablan

We present an enhanced prime decomposition theorem for knots that gives the isotopy classes of composite knots that can be constructed from a given list of prime factors (allowing for the mirroring and orientation reversing for each…

Geometric Topology · Mathematics 2014-11-14 Matt Mastin

We introduce a method of computing biquandle brackets of oriented knots and links using a type of decorated trivalent spatial graphs we call trace diagrams. We identify algebraic conditions on the biquandle bracket coefficients for moving…

Geometric Topology · Mathematics 2017-10-31 Sam Nelson , Natsumi Oyamaguchi

The combinatorics of the BPHZ subtraction scheme for a class of ladder graphs for the three point vertex in $\phi^3$ theory is transcribed into certain connectivity relations for marked chord diagrams (knots with transversal intersections).…

High Energy Physics - Theory · Physics 2015-06-26 Ioannis Tsohantjis , Alex C Kalloniatis , Peter D Jarvis

In this paper, we employ a ray-tracing algorithm to simulate the shadows of three equal-mass black holes in static equilibrium across a wide parameter space. We find that the shadows consist of a larger primary shadow and several distorted,…

General Relativity and Quantum Cosmology · Physics 2025-08-19 Dan Li , Yuxiang Zuo , Shiyang Hu , Chen Deng , Yu Wang , Wenfu Cao

In this article we discuss applications of neural networks to recognising knots and, in particular, to the unknotting problem. One of motivations for this study is to understand how neural networks work on the example of a problem for which…

Geometric Topology · Mathematics 2022-11-28 L. H. Kauffman , N. E. Russkikh , I. A. Taimanov

A well-known algorithm for unknotting knots involves traversing a knot diagram and changing each crossing that is first encountered from below. The minimal number of crossings changed in this way across all diagrams for a knot is called the…

Geometric Topology · Mathematics 2024-09-27 Lowell Davis , Jeffrey Meier

We use idempotents in quandle rings in combination with the state sum invariants of knots to distinguish all of the 12965 prime oriented knots up to 13 crossings using only 21 connected quandles and three quandles made of idempotents in…

Geometric Topology · Mathematics 2024-07-01 Mohamed Elhamdadi , Dipali Swain

We use grid diagrams to give a combinatorial algorithm for computing the knot Floer homology of the pullback of a knot K in its m-fold cyclic branched cover Sigma^m(K), and we give computations when m=2 for over fifty three-bridge knots…

Geometric Topology · Mathematics 2016-01-20 Adam Simon Levine

Set representations are the foundation of various set-based approaches in state estimation, reachability analysis and fault diagnosis. In this paper, we investigate spectrahedral shadows, a class of nonlinear geometric objects previously…

Systems and Control · Electrical Eng. & Systems 2025-04-15 Chengrui Wang , Haohao Qiu , Sibo Yao , James Lam

We present, to the best of the authors' knowledge, all known results for the (planar) crossing numbers of specific graphs and graph families. The results are separated into various categories; specifically, results for general graph…

Combinatorics · Mathematics 2021-12-09 Kieran Clancy , Michael Haythorpe , Alex Newcombe

We present the complete classification of the subgroup of the classical knot concordance group generated by knots with eight or fewer crossings. Proofs are presented in summary. We also describe extensions of this work to the case of nine…

Geometric Topology · Mathematics 2020-09-01 Julia Collins , Paul Kirk , Charles Livingston

Many natural counting problems arise in connection with the normal form of braids--and seem to have never been considered so far. Here we solve some of them by analysing the normality condition in terms of the associated permutations, their…

Combinatorics · Mathematics 2007-05-23 Patrick Dehornoy