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

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In this paper we provide new necessary and sufficient conditions for the existence of K\"ahler-Einstein metrics on small deformations of a Fano K\"ahler-Einstein manifold. We also show that the Weil-Petersson metric can be approximated by…

Differential Geometry · Mathematics 2024-03-12 Huai-Dong Cao , Xiaofeng Sun , Shing-Tung Yau , Yingying Zhang

In this paper we solve the general case of the cohomological relative index problem for foliations of non-compact manifolds. In particular, we significantly generalize the groundbreaking results of Gromov and Lawson, [GL83], to Dirac…

Differential Geometry · Mathematics 2024-02-19 Moulay Tahar Benameur , James L. Heitsch

This is a continuation to the paper [arXiv:1511.08164] in which a problem of minimizing normalized volumes over $\mathbb{Q}$-Gorenstein klt singularities was proposed. Here we consider its relation with K-semistability, which is an…

Algebraic Geometry · Mathematics 2018-02-21 Chi Li

A $C^0$-Finsler structure is a continuous function $F:TM \rightarrow [0,\infty)$ defined on the tangent bundle of a differentiable manifold $M$ such that its restriction to each tangent space is an asymmetric norm. We use the convolution of…

Differential Geometry · Mathematics 2020-06-19 Ryuichi Fukuoka , Anderson Macedo Setti

We show that topological amenability of an action of a countable discrete group on a compact space is equivalent to the existence of an invariant mean for the action. We prove also that this is equivalent to vanishing of bounded cohomology…

Group Theory · Mathematics 2010-04-05 Jacek Brodzki , Graham A. Niblo , Piotr Nowak , Nick Wright

In this paper, we study affine manifolds endowed with linear foliations. These are foliations defined by vector subspaces invariant by the linear holonomy. We show that an $n$-dimensional compact, complete, and oriented affine manifold…

Differential Geometry · Mathematics 2021-07-06 Tsemo Aristide

A linear system of difference equations and a nonlinear perturbation are considered. We propose sufficient conditions to ensure that the homeomorphism of topological equivalence between them is actually a $C^1$ diffeomorphism. These…

Dynamical Systems · Mathematics 2021-05-03 Álvaro Castañeda , Néstor Jara

The purpose of this note is twofold. In the first part we observe that two finitely generated non-amenable groups are quasi-isometric if and only if they admit topologically orbit equivalent Cantor minimal actions. In particular, free…

Dynamical Systems · Mathematics 2017-06-21 Kostya Medynets , Roman Sauer , Andreas Thom

We study left-invariant foliations ${\mathcal F}$ on semi-Riemannian Lie groups $G$ generated by a subgroup $K$. We are interested in such foliations which are conformal and with minimal leaves of codimension two. We classify such…

Differential Geometry · Mathematics 2020-12-17 Elsa Ghandour , Sigmundur Gudmundsson , Victor Ottosson

Is a sequence of Riemannian manifolds with positive scalar curvature, satisfying some conditions to keep the sequence reasonable, compact? What topology should one use for the convergence and what is the regularity of the limit space? In…

Differential Geometry · Mathematics 2024-06-07 Brian Allen , Wenchuan Tian , Changliang Wang

Let (M, F) be a compact codimension-one foliated manifold whose leaves are equipped with Riemannian metrics, and consider continuous functions on M that are harmonic along the leaves of F . If every such function is constant on leaves we…

Dynamical Systems · Mathematics 2007-12-14 Sergio Fenley , Renato Feres , Kamlesh Parwani

We establish some important inequalities under a lower weighted Ricci curvature bound on Finsler manifolds. Firstly, we establish a relative volume comparison of Bishop-Gromov type. As one of the applications, we obtain an upper bound for…

Differential Geometry · Mathematics 2021-07-16 Xinyue Cheng , Zhongmin Shen

We show that every quasiconformal contact foliation supports an invariant metric and characterise such foliations by the dynamical property of $C^1$-equicontinuity. We prove that a generalisation of the Weinstein conjecture holds for…

Dynamical Systems · Mathematics 2023-06-29 Douglas Finamore

We show that the universal minimimal proximal flow and the universal minimal strongly proximal flow of a discrete group can be realized as the Stone spaces of translation invariant Boolean algebras of subsets of the group satisfying a…

Group Theory · Mathematics 2021-01-19 Matthew Kennedy , Sven Raum , Guy Salomon

Let $m(G)$ be the infimum of the volumes of all open subgroups of a unimodular locally compact group $G$. Suppose integrable functions $\phi_1 , \phi_2 \colon G \to [0,1]$ satisfy $\| \phi_1 \| \leq \| \phi_2 \|$ and $\| \phi_1 \| + \|…

Metric Geometry · Mathematics 2023-02-21 Takashi Satomi

A version of the tangential LS category is introduced for topological laminations with a transverse invariant measure. Here, we use the transverse measure of the contraction of a tangential categorical open set instead of counting this set.…

Dynamical Systems · Mathematics 2012-07-13 Carlos Meniño Cotón

We study amenability of definable and topological groups. Among our main technical tools is an elaboration on and strengthening of the Massicot-Wagner version of the stabilizer theorem, and some results around measures. As an application we…

Logic · Mathematics 2021-11-23 Ehud Hrushovski , Krzysztof Krupiński , Anand Pillay

We give a sufficient condition for a metric (homology) manifold to be locally bi-Lipschitz equivalent to an open subset in $\rn$. The condition is a Sobolev condition for a measurable coframe of flat 1-forms. In combination with an earlier…

Metric Geometry · Mathematics 2011-03-17 Juha Heinonen , Stephen Keith

This paper, which is an outgrowth of a previous paper of the authors, continues the study of dimension 1 foliations on non-metrisable manifolds emphasising some anomalous behaviours. We exhibit surfaces with various extra properties like…

General Topology · Mathematics 2013-03-28 Mathieu Baillif , Alexandre Gabard , David Gauld

We show that the minimal volume entropy of closed manifolds remains unaffected when nonessential manifolds are added in a connected sum. We combine this result with the stable cohomotopy invariant of Bauer-Furuta in order to present an…

Differential Geometry · Mathematics 2022-02-15 Michael Brunnbauer , Masashi Ishida , Pablo Suárez-Serrato