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Related papers: Minimal F{\o}lner foliations are amenable

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In this note we give a characterization of taut Riemannian foliations using the transverse divergence. This result turns out to be a convenient tool in the case of some standard examples. Furthermore, we show that a classical tautness…

Differential Geometry · Mathematics 2016-02-10 Vladimir Slesar

Given a Fell bundle $\B$, over a discrete group $\Gamma$, we construct its reduced cross sectional algebra $C^*_r(\B)$, in analogy with the reduced crossed products defined for C*-dynamical systems. When the reduced and full cross sectional…

funct-an · Mathematics 2008-02-03 Ruy Exel

In analogy with ordinary simplicial volume, we show that integral foliated simplicial volume of oriented closed connected aspherical $n$-manifolds that admit an open amenable cover of multiplicity at most $n$ is zero. This implies that the…

Geometric Topology · Mathematics 2022-06-14 Clara Loeh , Marco Moraschini , Roman Sauer

Hausdorff Morita equivalence is an equivalence relation on singular foliations, which induces a bijection between their leaves. Our main statement is that linearizability along a leaf is invariant under Hausdorff Morita equivalence. The…

Differential Geometry · Mathematics 2026-02-19 Marco Zambon

Given a closed Riemannian manifold M and a (virtual) epimorphism from the fundamental group of M onto a free group of rank 2, we construct a tower of finite sheeted regular covers {M_n}_{n=0}^{\infty} of M such that the first non-zero…

Group Theory · Mathematics 2010-09-13 Goulnara Arzhantseva , Erik Guentner

Let $f$ be a $C^2$ partially hyperbolic diffeomorphisms of ${\mathbb T}^3$ (not necessarily volume preserving or transitive) isotopic to a linear Anosov diffeomorphism $A$ with eigenvalues $$\lambda_{s}<1<\lambda_{c}<\lambda_{u}.$$ Under…

Dynamical Systems · Mathematics 2021-11-16 Jana Rodriguez Hertz , Raúl Ures , Jiagang Yang

In this work, we develop shape expansions of minimal matchbox manifolds without holonomy, in terms of branched manifolds formed from their leaves. Our approach is based on the method of coding the holonomy groups for the foliated spaces, to…

Dynamical Systems · Mathematics 2014-02-07 Alex Clark , Steve Hurder , Olga Lukina

A transitive compact foliated space is shown to be a Riemannian foliation if and only if it is locally connected, finite dimensional, strongly equicontinuous and quasi-analytic, and the closure of its holonomy pseudogroup is quasi-analytic.

Geometric Topology · Mathematics 2013-11-15 Jesús A. Álvarez López , Alberto Candel

Working within the framework of free actions of countable amenable groups on compact metrizable spaces, we show that the small boundary property is equivalent to a density version of almost finiteness, which we call almost finiteness in…

Operator Algebras · Mathematics 2022-02-22 David Kerr , Gabor Szabo

Let $\mathcal F$ be a foliation on a smooth projective surface $S$ over the complex number $\mathbb{C}$. We introduce three birational non-negative invariants $c_1^2(\mathcal F)$, $c_2(\mathcal F)$ and $\chi(\mathcal F)$, called the Chern…

Algebraic Geometry · Mathematics 2024-10-08 Xin Lü , Shengli Tan

Let $M$ be a Fano manifold equipped with a K\"ahler form $\omega\in 2\pi c_1(M)$ and $K$ a connected compact Lie group acting on $M$ as holomorphic isometries. In this paper, we show the minimality of a $K$-invariant Lagrangian submanifold…

Differential Geometry · Mathematics 2017-10-27 Toru Kajigaya

We produce some explicit examples of conformally compact Einstein manifolds, whose conformal compactifications are foliated by Riemannian products of a closed Einstein manifold with the total space of a principal circle bundle over products…

Differential Geometry · Mathematics 2009-10-27 Dezhong Chen

In this paper we prove symmetry results for minimizers of a non coercive functional defined on the class of Sobolev functions with zero mean value. We prove that the minimizers are foliated Schwarz symmetric, i.e. they are axially symmetric…

Analysis of PDEs · Mathematics 2017-08-24 F Brock , G Croce , O Guibé , A Mercaldo

We prove that if a metric measure space satisfies the volume doubling condition and the Caffarelli-Kohn-Nirenberg inequality with the same exponent $n \ge 3$, then it has exactly the $n$-dimensional volume growth. As an application, if an…

Differential Geometry · Mathematics 2014-03-06 Alexandru Kristály , Shin-ichi Ohta

In the present article we review an approximation procedure for amenable traces on unital and separable C*-algebras acting on a Hilbert space in terms of F\o lner sequences of non-zero finite rank projections. We apply this method to…

Operator Algebras · Mathematics 2013-10-17 Pere Ara , Fernando Lledó

Let $\mathcal{F}$ be a compact Hausdorff foliation on a compact manifold. Let ${E_2^{>0,\bullet}}=\oplus\{E_2^{p,q}\colon p>0,q\geq 0\}$ be the subalgebra of cohomology classes with positive transverse degree in the $E_2$ term of the…

Algebraic Topology · Mathematics 2008-12-31 E. Macías-Virgós

Let $\mathcal{F}$ be a transversely orientable codimension one minimal foliation without vanishing cycles of a manifold $M$. We show that if the fundamental group of each leaf of $\mathcal{F}$ has polynomial growth of degree $k$ for some…

Geometric Topology · Mathematics 2017-07-19 Tomoo Yokoyama

We prove that the restriction of a probability measure invariant under a nonhyperbolic, ergodic and totally irreducible automorphism of a compact connected abelian group to the leaves of the central foliation is severely restricted. We also…

Dynamical Systems · Mathematics 2007-05-23 Elon Lindenstrauss , Klaus Schmidt

The notions of the interior and truncated connections of a nonholonomic manifold are introduced. A class of extended truncated connections is distinguished. For the case of a contact space with a Finsler metric, it is shown that there…

Differential Geometry · Mathematics 2011-03-23 Sergey V. Galaev

Amenability of any of the algebras described in the title is known to force them to be finite-dimensional. The analogous problems for \emph{approximate} amenability have been open for some years now. In this article we give a complete…

Functional Analysis · Mathematics 2011-04-11 Yemon Choi , Fereidoun Ghahramani