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Related papers: Braid ordering and knot genus

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The slicing number of a knot, $u_s(K)$, is the minimum number of crossing changes required to convert $K$ to a slice knot. This invariant is bounded above by the unknotting number and below by the slice genus $g_s(K)$. We show that for many…

Geometric Topology · Mathematics 2008-02-18 Brendan Owens

We give an explicit geometric argument that Artin's braid group $B_n$ is right-orderable. The construction is elementary, natural, and leads to a new, effectively computable, canonical form for braids which we call left-consistent canonical…

Geometric Topology · Mathematics 2016-09-07 Roger Fenn , Michael T Greene , Dale Rolfsen , Colin Rourke , Bert Wiest

In the 1920's Artin defined the braid group in an attempt to understand knots in a more algebraic setting. A braid is a certain arrangement of strings in three-dimensional space. It is a celebrated theorem of Alexander that every knot is…

Geometric Topology · Mathematics 2011-10-05 Stephen Bigelow , Eric Ramos , Ren Yi

In this paper, we investigate three geometrical invariants of knots, the height, the trunk and the representativity. First, we give a conterexample for the conjecture which states that the height is additive under connected sum of knots. We…

Geometric Topology · Mathematics 2017-09-22 Ryan Blair , Makoto Ozawa

We introduce a 4-dimensional analogue of the rational Seifert genus of a knot $K\subset Y$, which we call the rational slice genus, that measures the complexity of a homology class in $H_2(Y\times [0,1],K;\mathbb{Q})$. Our main theorem is a…

Geometric Topology · Mathematics 2023-09-01 Katherine Raoux , Matthew Hedden

A geometric argument is given to prove that the Seifert genus of a positive knot equals its slice genus. A combinatorial invariant, giving a lower bound for the slice genus, is formulated for arbitrary knots. Properties and applications of…

Geometric Topology · Mathematics 2012-05-22 Vyacheslav Krushkal

It is well known that there exist knots with Seifert surfaces of arbitrarily high genus. In this paper, we show the existence of infinitely many knot exteriors where each of which has longitudinal essential surfaces of any positive genus…

Geometric Topology · Mathematics 2025-08-26 Joao M. Nogueira

Although most knots are nonalternating, modern research in knot theory seems to focus on alternating knots. We consider here nonalternating knots and their properties. Specifically, we show certain classes of knots have nontrivial Jones…

Geometric Topology · Mathematics 2009-07-13 Neil R. Nicholson

We study the double slice genus of a knot, a natural generalization of slice genus. We define a notion called band number, a natural generalization of band unknotting number, and prove it is an upper bound on double slice genus. Our bound…

Geometric Topology · Mathematics 2019-01-24 Clayton McDonald

Dehornoy showed that the Artin braid groups $B_n$ are left-orderable. This ordering is discrete, but we show that, for $n >2$ the Dehornoy ordering, when restricted to certain natural subgroups, becomes a dense ordering. Among subgroups…

Group Theory · Mathematics 2007-05-23 Adam Clay , Dale Rolfsen

We present a topological interpretation of knot and braid contact homology in degree zero, in terms of cords and skein relations. This interpretation allows us to extend the knot invariant to embedded graphs and higher-dimensional knots. We…

Geometric Topology · Mathematics 2014-11-11 Lenhard Ng

We study cosmetic crossings in knots of genus one and obtain obstructions to such crossings in terms of knot invariants determined by Seifert matrices. In particular, we prove that for genus one knots the Alexander polynomial and the…

Geometric Topology · Mathematics 2013-06-24 Cheryl Balm , Stefan Friedl , Efstratia Kalfagianni , Mark Powell

We show that for genus one knots the Alexander polynomial and the homology of the double cover branching over the knot provide obstructions to cosmetic crossings. As an application we prove the nugatory crossing conjecture for the…

Geometric Topology · Mathematics 2011-07-12 Cheryl Balm , Efstratia Kalfagianni

A chord diagram consists of a circle, called the backbone, with line segments, called chords, whose endpoints are attached to distinct points on the circle. The genus of a chord diagram is the genus of the orientable surface obtained by…

Geometric Topology · Mathematics 2016-04-15 Jonathan Burns , Nataša Jonoska , Masahico Saito

We prove that the so-called t algebra of braids and ties supports a Markov trace. Further, by using this trace in the Jones' recipe, we define invariant polynomials for classical knots and singular knots. Our invariants have three…

Geometric Topology · Mathematics 2016-04-26 Francesca Aicardi , Jesus Juyumaya

The braid axis of a closed 3-braid lifts to a genus one fibered knot in the double cover of S^3 branched over the closed braid. Every (null homologous) genus one fibered knot in a 3-manifold may be obtained in this way. Using this…

Geometric Topology · Mathematics 2007-05-23 Kenneth L. Baker

A knot in the 3-sphere in genus-1 1-bridge position (called a (1,1)-position) can be described by an element of the braid group of two points in the torus. Our main results tell how to translate between a braid group element and the…

Geometric Topology · Mathematics 2011-08-05 Sangbum Cho , Darryl McCullough

This article is about Artin's braid group and its role in knot theory. We set ourselves two goals: (i) to provide enough of the essential background so that our review would be accessible to graduate students, and (ii) to focus on those…

Geometric Topology · Mathematics 2007-05-23 Joan S. Birman , Tara E. Brendle

For some families of two-bridge knots, including double-twist knots with genus at least four, we determine precisely the set of integers $n>1$ such that the fundamental group of the $n$-fold cyclic branched cover of the 3-sphere along these…

Geometric Topology · Mathematics 2020-02-26 Hannah Turner

We classify 3-braid knots whose topological 4-genus coincides with their Seifert genus, using McCoy's twisting method and the Xu normal form. In addition, we give upper bounds for the topological 4-genus of positive and strongly…

Geometric Topology · Mathematics 2024-03-29 Sebastian Baader , Lukas Lewark , Filip Misev , Paula Truöl