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Twisted torus links are given by twisting a subset of strands on a closed braid representative of a torus link. T--links are a natural generalization, given by repeated positive twisting. We establish a one-to-one correspondence between…

Geometric Topology · Mathematics 2014-02-26 Joan Birman , Ilya Kofman

Building on work by Alishahi-Dowlin, we extract a new knot invariant $\lambda \ge 0$ from universal Khovanov homology. While $\lambda$ is a lower bound for the unknotting number, in fact more is true: $\lambda$ is a lower bound for the…

Geometric Topology · Mathematics 2025-11-27 Damian Iltgen , Lukas Lewark , Laura Marino

In this paper we solve one open problem from \cite{pat} and give some generalizations. Namely, we prove that the first homology group of positive braid knot is trivial. Also, we show that the same is true for the Khovanov-Rozansky homology…

Quantum Algebra · Mathematics 2007-05-23 Marko Stosic

The lattice stick number of knots is defined to be the minimal number of straight sticks in the cubic lattice required to construct a lattice stick presentation of the knot. We similarly define the lattice stick number $s_{L}(G)$ of spatial…

Geometric Topology · Mathematics 2018-06-27 Hyungkee Yoo , Chaeryn Lee , Seungsang Oh

For a knot K in S^3, let T(K) be the characteristic toric sub-orbifold of the orbifold (S^3,K) as defined by Bonahon and Siebenmann. If K has unknotting number one, we show that an unknotting arc for K can always be found which is disjoint…

Geometric Topology · Mathematics 2009-06-30 Cameron McA Gordon , John Luecke

Symmetries of knots have been studied extensively, and strongly invertible knots are one of them. Lamm defined the equivariant crossing number $c_t(K)$, the minimum crossing number among all symmetric diagrams for a strongly invertible knot…

Geometric Topology · Mathematics 2023-04-04 Jundai Nanasawa

The concordance orders of many algebraic order two knots of ten or fewer crossings have been heretofore unknown. We use Casson-Gordon invariants and twisted Alexander polynomials to find that, in all but one case, these knots do not have…

Geometric Topology · Mathematics 2007-05-23 Andrius Tamulis

This paper is about the clock number of a knot. First we define the clock number by using states of a knot defined by Kauffman. Next we show that if K is a prime knot, its clock number is greater than or equal to its crossing number.…

Geometric Topology · Mathematics 2011-03-02 Yukiko Abe

A long standing open conjecture states that if a link $\mathcal{K}$ is alternating, then its ropelength $L(\mathcal{K})$ is at least of the order $O(Cr(\mathcal{K}))$. A recent result shows that the maximum braid index of a link bounds the…

Geometric Topology · Mathematics 2021-08-25 Yuanan Diao

Region crossing change for a knot or a proper link is an unknotting operation. In this paper, we provide a sharp upper bound on the region unknotting number for a large class of torus knots and proper links. Also, we discuss conditions on…

Geometric Topology · Mathematics 2013-05-30 Vikash Siwach , Madeti Prabhakar

It is found that the number, $M_n$, of irreducible multiple zeta values (MZVs) of weight $n$, is generated by $1-x^2-x^3=\prod_n (1-x^n)^{M_n}$. For $9\ge n\ge3$, $M_n$ enumerates positive knots with $n$ crossings. Positive knots to which…

High Energy Physics - Theory · Physics 2009-10-30 D. J. Broadhurst , D. Kreimer

The lattice stick number of a knot type is defined to be the minimal number of straight line segments required to construct a polygon presentation of the knot type in the cubic lattice. In this paper, we mathematically prove that the…

Geometric Topology · Mathematics 2015-12-14 Youngsik Huh , Seungsang Oh

We classify knot traces with trisection genus at most 2. We give infinitely many knots whose traces have trisection genus 3, and infinitely many knots whose traces have trisection genus 4. We also show that there exist infinite families of…

Geometric Topology · Mathematics 2026-05-29 Natsuya Takahashi

In this paper, we define a lassoing on a link, a local addition of a trivial knot to a link. Let K be an s-component link with the Conway polynomial non-zero. Let L be a link which is obtained from K by r-iterated lassoings. The complete…

Geometric Topology · Mathematics 2011-01-04 Ayaka Shimizu

We define the virtual bridge number $vb(K)$ and the virtual unknotting number $vu(K)$ invariants for virtual knots. For ordinary knots $K$ they are closely related to the bridge number $b(K)$ and the unknotting number $u(K)$ and we have…

Geometric Topology · Mathematics 2014-04-24 Evarist Byberi , Vladimir Chernov

Every knot can be embedded in the union of finitely many half planes with a common boundary line in such a way that the portion of the knot in each half plane is a properly embedded arc. The minimal number of such half planes is called the…

Geometric Topology · Mathematics 2010-10-15 Gyo Taek Jin , Wang Keun Park

We show that twisted torus knots $T(p,q,3,s)$ are tunnel number one. A short spanning arc connecting two adjacent twisted strands is an unknotting tunnel.

Geometric Topology · Mathematics 2010-01-18 Jung Hoon Lee

In this article we study the braid indices of 2-bridge knots with a fixed crossing number $c$. We show that the average braid index of the set of $2$-bridge knots of crossing number $c$ is asymptotically linear, approaching…

Geometric Topology · Mathematics 2024-01-17 Tobias Clark , Jeremy Frank , Adam M. Lowrance

We present a systematic classification of uncolored bonded knots with singularity number at most seven. Bonded knots provide a topological model for closed protein chains with intramolecular bridges, such as disulfide bonds. Following the…

Geometric Topology · Mathematics 2026-03-20 Boštjan Gabrovšek , Matic Simonič , Wanda Niemyska

In this work, we find a closed form formula for the braid index of an $n$-bridge braid, a class of positive braid knots which simultaneously generalizes torus knots, 1-bridge braids, and twisted torus knots. Our proof is elementary,…

Geometric Topology · Mathematics 2023-09-12 Dane Gollero , Siddhi Krishna , Marissa Loving , Viridiana Neri , Izah Tahir , Len White