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Jones polynomials, volume and essential knot surfaces: a survey

David Futer, Efstratia Kalfagianni, Jessica S. Purcell (2014)

Banach Center Publications

This paper is a brief overview of recent results by the authors relating colored Jones polynomials to geometric topology. The proofs of these results appear in the papers [18, 19], while this survey focuses on the main ideas and examples.

Knot manifolds with isomorphic spines

Alberto Cavicchioli, Friedrich Hegenbarth (1994)

Fundamenta Mathematicae

We study the relation between the concept of spine and the representation of orientable bordered 3-manifolds by Heegaard diagrams. As a consequence, we show that composing invertible non-amphicheiral knots yields examples of topologically different knot manifolds with isomorphic spines. These results are related to some questions listed in [9], [11] and recover the main theorem of [10] as a corollary. Finally, an application concerning knot manifolds of composite knots with h prime factors completes...

Le genre de Heegaard de 3-variétés orientables.

Phoebe Hoidn (1996)

Revista Matemática de la Universidad Complutense de Madrid

We consider irreducible, closed, oriented, connected 3-manifolds with a nontrivial fundamental group, and link Heegaard genus to fundamental domains. We shall show that the Heegaard genus is the least positive integer h(M) for which the manifold has a fundamental domain with 2·h(M) faces.

Les invariants θ p des 3-variétés périodiques

Nafaa Chbili (2001)

Annales de l’institut Fourier

Soit r un entier > 1 . Une 3-variété M est dite r -périodique si et seulement si le groupe cyclique G = / r agit semi-librement sur M avec un cercle comme l’ensemble des points fixes. Dans cet article, nous utilisons les invariants quantiques θ p pour établir des conditions nécessaires pour qu’une 3-variété soit périodique.

Local moves on knots and products of knots

Louis H. Kauffman, Eiji Ogasa (2014)

Banach Center Publications

We show a relation between products of knots, which are generalized from the theory of isolated singularities of complex hypersurfaces, and local moves on knots in all dimensions. We discuss the following problem. Let K be a 1-knot which is obtained from another 1-knot J by a single crossing change (resp. pass-move). For a given knot A, what kind of relation do the products of knots, K ⊗ A and J ⊗ A, have? We characterize these kinds of relation between K ⊗ A and J ⊗ A by using local moves on high...

Malnormal subgroups and Frobenius groups: basics and examples

Pierre de la Harpe, Claude Weber (2014)

Confluentes Mathematici

Malnormal subgroups occur in various contexts. We review a large number of examples, and compare the general situation to that of finite Frobenius groups of permutations.In a companion paper [18], we analyse when peripheral subgroups of knot groups and 3 -manifold groups are malnormal.

Mapping class group of a handlebody

Bronisław Wajnryb (1998)

Fundamenta Mathematicae

Let B be a 3-dimensional handlebody of genus g. Let ℳ be the group of the isotopy classes of orientation preserving homeomorphisms of B. We construct a 2-dimensional simplicial complex X, connected and simply-connected, on which ℳ acts by simplicial transformations and has only a finite number of orbits. From this action we derive an explicit finite presentation of ℳ.

Currently displaying 201 – 220 of 454