English
Related papers

Related papers: Tame combing and almost convexity conditions

200 papers

We introduce a combinatorial property for finitely generated groups called stackable that implies the existence of an inductive procedure for constructing van Kampen diagrams with respect to a canonical finite presentation. We also define…

Group Theory · Mathematics 2012-01-04 Mark Brittenham , Susan Hermiller

A new pair of asymptotic invariants for finitely presented groups, called intrinsic and extrinsic tame filling functions, are introduced. These filling functions are quasi-isometry invariants that strengthen the notions of intrinsic and…

Group Theory · Mathematics 2014-10-13 Mark Brittenham , Susan Hermiller

We prove that Thompson's group F is not minimally almost convex with respect to any generating set which is a subset of the standard infinite generating set for F and which contains x_1. We use this to show that F is not almost convex with…

Group Theory · Mathematics 2021-09-24 Matthew Horak , Melanie Stein , Jennifer Taback

We continue our study of ends of non-compact manifolds, with a focus on the inward tameness condition. For manifolds with compact boundary, inward tameness, has significant implications. For example, such manifolds have stable homology at…

Geometric Topology · Mathematics 2017-04-19 Craig R. Guilbault , Frederick C. Tinsley

We prove that Richard Thompson's group F is not minimally almost convex with respect to the two standard generators. This improves upon a recent result of S. Cleary and J. Taback. We make use of the forest diagrams for elements of F…

Group Theory · Mathematics 2007-05-23 James Belk , Kai-Uwe Bux

Let $(X,G)$ be a minimal equicontinuous dynamical system, where $X$ is a compact metric space and $G$ some topological group acting on $X$. Under very mild assumptions, we show that the class of regular almost automorphic extensions of…

Dynamical Systems · Mathematics 2019-11-13 Gabriel Fuhrmann , Dominik Kwietniak

We introduce certain homology and cohomology subgroups for any almost complex structure and study their pureness, fullness and duality properties. Motivated by a question of Donaldson, we use these groups to relate J-tamed symplectic cones…

Symplectic Geometry · Mathematics 2009-09-15 Tian-Jun Li , Weiyi Zhang

In this article we show that the Baumslag-Solitar group $BS(1,2)$ is minimally almost convex, or $MAC$. We also show that $BS(1,2)$ does not satisfy Po\'enaru's almost convexity condition $P(2)$, and hence the condition $P(2)$ is strictly…

Group Theory · Mathematics 2014-08-05 Murray Elder , Susan Hermiller

We study classes of right-angled Coxeter groups with respect to the strong submodel relation of parabolic subgroup. We show that the class of all right-angled Coxeter group is not smooth, and establish some general combinatorial criteria…

Logic · Mathematics 2019-12-19 Tapani Hyttinen , Gianluca Paolini

The aim of this paper is to construct formal normal forms for the class of topologically quasi-homogeneous foliations under generic conditions. Any such normal form is given as the sum of three terms: an initial generic quasi-homogeneous…

Dynamical Systems · Mathematics 2013-09-06 Truong Hong Minh

We construct new families of groups with property (T) and infinitely many alternating group quotients. One of those consists of subgroups of $\mathrm{Aut}(\mathbf F_{p}[x_1, \dots, x_n])$ generated by a suitable set of tame automorphisms.…

Group Theory · Mathematics 2023-05-29 Pierre-Emmanuel Caprace , Martin Kassabov

We demonstrate the existence of a family of finitely generated subgroups of Richard Thompson's group $F$ which is strictly well-ordered by the embeddability relation in type $\epsilon_0 +1$. All except the maximum element of this family…

Group Theory · Mathematics 2021-02-09 Collin Bleak , Matthew G. Brin , Justin Tatch Moore

We introduce a class of thin combings and prove that it has a nice behaviour in free constructions. Among corollaries, we deduce the relative metabolicity, in the sense of Gersten, of Sela's limit groups.

Group Theory · Mathematics 2007-05-23 Francois Dahmani

We extend the notion of a tame covering of a pair (X,D) where X is a regular scheme and D is a normal crossing divisor (cf. SGA1), to pairs (X,Y) where X is an arbitrary scheme and Y is a closed subset in X. We show that the abelianized…

Number Theory · Mathematics 2007-05-23 Alexander Schmidt

In this paper we continue an earlier study of ends non-compact manifolds. The over-arching goal is to investigate and obtain generalizations of Siebenmann's famous collaring theorem that may be applied to manifolds having non-stable…

Geometric Topology · Mathematics 2014-11-11 C R Guilbault , F C Tinsley

We prove the existence of strongly tame sets in affine algebraic homogenenous spaces of linear algebraic Lie groups. We also show that $(\mathbb{C}^n,A)$ for a discrete tame set enjoy the relative density property, and we provide examples…

Complex Variables · Mathematics 2022-12-21 Rafael B. Andrist , Riccardo Ugolini

We obtain many results and solve some problems about feebly compact paratopological groups. We obtain necessary and sufficient conditions for such a group to be topological. One of them is the quasiregularity. We prove that each…

Group Theory · Mathematics 2020-08-05 Taras Banakh , Alex Ravsky

For a quasi-projective scheme $X$ admitting a smooth compactification over a local field of residue characteristic $p > 0$, we construct a continuous reciprocity homomorphism from a tame class group to the abelian tame etale fundamental…

Algebraic Geometry · Mathematics 2026-01-21 Rahul Gupta , Amalendu Krishna , Jitendra Rathore

We study topological full groups attached to groupoid models for left regular representations of Garside categories. Groups arising in this way include Thompson's group $V$ and many of its variations such as R\"over-Nekrashevych groups. Our…

Operator Algebras · Mathematics 2024-10-15 Xin Li

We establish a "matrix simultaneous diagonalization theorem" for disconnected reductive groups which relaxes both the semisimplicity condition and the commutativity condition. As an application, we prove the following basic results…

Number Theory · Mathematics 2023-10-12 Zhongyipan Lin
‹ Prev 1 2 3 10 Next ›