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We introduce new sufficient conditions for intrinsic knotting and linking. A graph on n vertices with at least 4n-9 edges is intrinsically linked. A graph on n vertices with at least 5n-14 edges is intrinsically knotted. We also classify…

Geometric Topology · Mathematics 2007-05-23 J. Campbell , T. W. Mattman , R. Ottman , J. Pyzer , M. Rodrigues , S. Williams

A polynomial knot is a smooth embedding $\kappa: \real \to \real^n$ whose components are polynomials. The case $n = 3$ is of particular interest. It is both an object of real algebraic geometry as well as being an open ended topological…

Geometric Topology · Mathematics 2007-05-23 Alan Durfee , Donal O'Shea

The space of n-sided polygons embedded in three-space consists of a smooth manifold in which points correspond to piecewise linear or ``geometric'' knots, while paths correspond to isotopies which preserve the geometric structure of these…

Geometric Topology · Mathematics 2009-09-25 Jorge Alberto Calvo

In 1983 Conway and Gordon proved that any embedding of the complete graph $K_7$ into $\mathbb{R}^3$ contains at least one nontrivial knot as its Hamiltonian cycle. After their work knots (also links) are considered as intrinsic properties…

Geometric Topology · Mathematics 2011-03-08 Youngsik Huh

The stick number and the edge length of a knot type in the simple hexagonal lattice (sh-lattice) are the minimal numbers of sticks and edges required, respectively, to construct a knot of the given type in sh-lattice. By introducing a…

Geometric Topology · Mathematics 2024-03-07 Yueheng Bao , Ari Benveniste , Marion Campisi , Nicholas Cazet , Ansel Goh , Jiantong Liu , Ethan Sherman

The curves of zero intensity of a complex optical field can form knots and links: optical vortex knots. Both theoretical constructions and experiments have so far been restricted to the very small families of torus knots or lemniscate…

Geometric Topology · Mathematics 2024-07-30 Benjamin Bode

We investigate the minimal number of links and knots in complete partite graphs. We provide exact values or bounds on the minimal number of links for all complete partite graphs with all but 4 vertices in one partition, or with 9 vertices…

Geometric Topology · Mathematics 2014-12-24 Loren Abrams , Blake Mellor , Lowell Trott

A graph is said to be orthogonalisable if the set of real symmetric matrices whose off-diagonal pattern is prescribed by its edges contains an orthogonal matrix. We determine some necessary and some sufficient conditions on the sizes of the…

Combinatorics · Mathematics 2025-06-16 Rupert H. Levene , Polona Oblak , Helena Šmigoc

We present evidence in support of a conjecture that a bipartite graph with at least five vertices in each part and |E(G)| \geq 4 |V(G)| - 17 is intrinsically knotted. We prove the conjecture for graphs that have exactly five or exactly six…

Geometric Topology · Mathematics 2008-11-04 Sophy Huck , Alexandra Appel , Miguel-Angel Manrique , Thomas W Mattman

We classify graphs that are 0, 1, or 2 edges short of being complete partite graphs with respect to intrinsic linking and intrinsic knotting. In addition, we classify intrinsic knotting of graphs on 8 vertices. For graphs in these families,…

Geometric Topology · Mathematics 2007-05-23 Thomas W. Mattman , Ryan Ottman , Matt Rodrigues

For a polygonal knot K, it is shown that a tube of radius R(K), the polygonal thickness radius, is an embedded torus. Given a thick configuration K, perturbations of size r<R(K) define satellite structures, or local knotting. We explore…

Geometric Topology · Mathematics 2007-05-23 Kenneth C. Millett , Michael Piatek , Eric J. Rawdon

The Rado-Horn theorem provides necessary and sufficient conditions for when a collection of vectors can be partitioned into a fixed number of linearly independent sets. Such partitions exist if and only if every subset of the vectors…

Functional Analysis · Mathematics 2011-12-02 Peter G. Casazza , Jesse Peterson

For a positive integer $n\ge 3$, the collection of $n$-sided polygons embedded in $3$-space defines the space of geometric knots. We will consider the subspace of equilateral knots, consisting of embedded $n$-sided polygons with unit length…

Geometric Topology · Mathematics 2018-10-30 Kathleen Hake

It has been suggested recently that knots might exist as stable soliton solutions in a simple three-dimensional classical field theory, opening up a wide range of possible applications in physics and beyond. We have re-examined and extended…

High Energy Physics - Theory · Physics 2008-11-26 Richard A. Battye , Paul M. Sutcliffe

In this paper we study rational real algebraic knots in $\R P^3$. We show that two real algebraic knots of degree $\leq5$ are rigidly isotopic if and only if their degrees and encomplexed writhes are equal. We also show that any irreducible…

Geometric Topology · Mathematics 2011-08-08 Johan Björklund

We define some physical variables associated with the traversing sequences of electrons along the orbit which is a 2D projection of 8$_{18}$-knot. The configuration is regular but the resulting contributions, which are related to the…

Quantum Physics · Physics 2007-05-23 A. Kwang-Hua Chu

We show that every heptagon is a section of a $3$-polytope with $6$ vertices. This implies that every $n$-gon with $n\geq 7$ can be obtained as a section of a $(2+\lfloor\frac{n}{7}\rfloor)$-dimensional polytope with at most…

Metric Geometry · Mathematics 2015-02-11 Arnau Padrol , Julian Pfeifle

We compose the table of knots in the thickened torus T x I having diagrams with at most 4 crossings. The knots are constructed by the three-step process. First we list regular graphs of degree 4 with at most 4 vertices, then for each graph…

Geometric Topology · Mathematics 2012-07-02 A. A. Akimova , S. V. Matveev

In this note we show that ribbon concordance forms a partial ordering on the set of knots, answering a question of Gordon. The proof makes use of representation varieties of the knot groups to $SO(N)$ and relations between them induced by a…

Geometric Topology · Mathematics 2022-01-12 Ian Agol

We show that all knots up to $6$ crossings can be represented by polynomial knots of degree at most $7$, among which except for $5_2, 5_2^*, 6_1, 6_1^*, 6_2, 6_2^*$ and $6_3$ all are in their minimal degree representation. We provide…

Geometric Topology · Mathematics 2021-01-05 Rama Mishra , Hitesh Raundal
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