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Related papers: Unknotting tunnels and Seifert surfaces

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This elementary article introduces easy-to-manage invariants of genus one knots in homology 3-spheres. To prove their invariance, we investigate properties of an invariant of 3-dimensional genus two homology handlebodies called the…

Geometric Topology · Mathematics 2025-12-02 Christine Lescop

We show that, for any integer $n\ge 3$, there is a prime knot $k$ such that (1) $k$ is not meridionally primitive, and (2) for every $m$-bridge knot $k'$ with $m\leq n$, the tunnel numbers satisfy $t(k\# k')\le t(k)$. This gives…

Geometric Topology · Mathematics 2013-10-23 Tao Li , Ruifeng Qiu

Expanding on work by Conway, Orson, and Powell, we study the isotopy classes rel. boundary of nonorientable, compact, locally flatly embedded surfaces in $D^4$ with knot group $\mathbb{Z}_2$. In particular we show that if two such surfaces…

Geometric Topology · Mathematics 2024-02-29 Mark Pencovitch

This manuscript introduces a new framework for the study of knots by exploring the neighborhood of knot embeddings in the space of simple open and closed curves in 3-space. The latter gives rise to a knotoid spectrum, which determines the…

Geometric Topology · Mathematics 2024-10-22 Eleni Panagiotou

We introduce a new numerical knot invariant, termed the \textit{segment number}, which is derived from partitioned knot diagrams subject to specific over/under-crossing constraints. We prove that a knot is non-trivial if and only if its…

Geometric Topology · Mathematics 2026-02-19 Makoto Ozawa

We introduce an invariant of a hyperbolic knot which is a map $\alpha\mapsto \boldsymbol{\Phi}_\alpha(h)$ from $\mathbb{Q}/\mathbb{Z}$ to matrices with entries in $\overline{\mathbb{Q}}[[h]]$ and with rows and columns indexed by the…

Geometric Topology · Mathematics 2024-06-25 Stavros Garoufalidis , Don Zagier

The probability of a random polygon (or a ring polymer) having a knot type $K$ should depend on the complexity of the knot $K$. Through computer simulation using knot invariants, we show that the knotting probability decreases exponentially…

Soft Condensed Matter · Physics 2009-11-07 Miyuki K. Shimamura , Tetsuo Deguchi

We define a group-valued invariant of virtual knots and relate it to various other group-valued invariants of virtual knots, including the extended group of Silver-Williams and the quandle group of Manturov and Bardakov-Bellingeri. A…

Geometric Topology · Mathematics 2017-07-14 Hans U. Boden , Robin Gaudreau , Eric Harper , Andrew J. Nicas , Lindsay White

This paper concerns pseudo-classical knots in the non-orientable manifold $\hat{\Sigma} =\Sigma \times [0,1]$, where $\Sigma$ is a non-orientable surface and a knot $K \subset \hat{\Sigma}$ is called pseudo-classical if $K$ is…

Geometric Topology · Mathematics 2024-07-31 Vladimir Tarkaev

Connected sum and trivalent vertex sum are natural operations on genus 2 spatial graphs and, as with knots, tunnel number behaves in interesting ways under these operations. We prove sharp Scharlemann-Schultens type bounds for the tunnel…

Geometric Topology · Mathematics 2021-11-10 Scott A. Taylor , Maggy Tomova

Using the Gordon-Litherland pairing, one can define invariants (signature, nullity, determinant) for ${\mathbb Z}/2$ null-homologous links in thickened surfaces. In this paper, we study the concordance properties of these invariants. For…

Geometric Topology · Mathematics 2021-11-16 Hans U. Boden , Homayun Karimi

Given integers g_i > 1 (i=1,...,n) we prove that there exist infinitely may knots K_i in S^3 so that g(E(K_i)) = g_i and the Heegaard genus of the exterior of the connected sum of K_1,...,K_n is the sum the Heegaard genera of K_1,...,K_n,…

Geometric Topology · Mathematics 2007-05-23 Tsuyoshi Kobayashi , Yo'av Rieck

Knot Floer homology is a knot invariant defined using holomorphic curves. In more recent work, taking cues from bordered Floer homology,the authors described another knot invariant, called "bordered knot Floer homology", which has an…

Geometric Topology · Mathematics 2019-12-05 Zoltan Szabo , Peter Ozsvath

We generalize the idea of unknotting knots to Seifert surfaces. We define an operation called ribbon twist which serves as the equivalent of a crossing change for knots. A Seifert surface is considered untwisted, the equivalent to…

Geometric Topology · Mathematics 2015-02-27 Michael Pfeuti

Simple closed curves in the plane can be mapped to nontrivial knots under the action of origami foldings that allow the paper to self-intersect. We show all tame knot types may be produced in this manner, motivating the development of a new…

Geometric Topology · Mathematics 2021-05-05 Joseph Slote , Thomas Bertschinger

Kauffman and Lomonaco explored the idea of understanding quantum entanglement (the non-local correlation of certain properties of particles) topologically by viewing unitary entangling operators as braiding operators. In the work of G.…

Geometric Topology · Mathematics 2018-08-01 Louis H. Kauffman , Eshan Mehrotra

We offer a pedestrian level review of the wall-crossing invariants. The story begins from the scattering theory in quantum mechanics where the spectrum reshuffling can be related to permutations of S-matrices. In non-trivial situations,…

High Energy Physics - Theory · Physics 2015-06-23 D. Galakhov , A. Mironov , A. Morozov

Let $K/\mathbf{Q}_p$ be a finite unramified extension, $\overline{\rho}:\mathrm{Gal}(\overline{\mathbf{Q}}_p/K)\rightarrow\mathrm{GL}_n(\overline{\mathbf{F}}_p)$ a continuous representation, and $\tau$ a tame inertial type of dimension $n$.…

Number Theory · Mathematics 2023-06-12 Daniel Le , Bao Le Hung , Stefano Morra , Chol Park , Zicheng Qian

By considering negative surgeries on a knot $K$ in $S^3$, we derive a lower bound to the non-orientable slice genus $\gamma_4(K)$ in terms of the signature $\sigma(K)$ and the concordance invariants $V_i(\overline{K})$, which strengthens a…

Geometric Topology · Mathematics 2016-07-28 Marco Golla , Marco Marengon

We provide a new proof of the following results of H. Schubert: If K is a satellite knot with companion J and pattern L that lies in a solid torus T in which it has index k, then the bridge numbers satisfy the following: 1) The bridge…

Geometric Topology · Mathematics 2007-05-23 Jennifer Schultens
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