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The spectral geometry of negatively curved manifolds has received more attention than its positive curvature counterpart. In this paper we will survey a variety of spectral geometry results that are known to hold in the context of…

Differential Geometry · Mathematics 2024-11-12 Emilio A. Lauret , Benjamin Linowitz

In the first part of this article, we study linear cones over totally ordered fields. We show that for each such cone there uniquely exists a universal vector space (called its spanned vector space) into which it embeds as a generating…

Metric Geometry · Mathematics 2025-08-26 Ethan Kharitonov , Argam Ohanyan

It is well known that positivity properties of the curvature of a vector bundle have implications on the algebro-geometric properties of the bundle, such as numerical positivity, vanishing of higher cohomology leading to existence of global…

Algebraic Geometry · Mathematics 2018-10-12 Mark Green , Phillip Griffiths

We prove that the following are equivalent for a locally compact group $G$: (i) $G$ is amenable; (ii) $M(G)$ is Connes-amenable; (iii) $M(G)$ has a normal, virtual diagonal.

Functional Analysis · Mathematics 2016-09-07 Volker Runde

Icosahedral shells undergo a buckling transition as the ratio of Young's modulus to bending stiffness increases. Strong bending stiffness favors smooth, nearly spherical shapes, while weak bending stiffness leads to a sharply faceted…

Biological Physics · Physics 2009-11-13 M. Widom , J. Lidmar , D. R. Nelson

The deformation theory of hyperbolic and Euclidean cone-manifolds with all cone angles less then 2{\pi} plays an important role in many problems in low dimensional topology and in the geometrization of 3-manifolds. Furthermore, various old…

Differential Geometry · Mathematics 2015-03-13 Rafe Mazzeo , Gregoire Montcouquiol

A polygonal surface in the pseudo-hyperbolic space H^(2,n) is a complete maximal surface bounded by a lightlike polygon in the Einstein universe Ein^(1,n) with finitely many vertices. In this article, we give several characterizations of…

Differential Geometry · Mathematics 2026-05-05 Alex Moriani

We discuss the validity of Minkowski integral identities for hypersurfaces inside a cone, intersecting the boundary of the cone orthogonally. In doing so we correct a formula provided in [3]. Then we study rigidity results for constant mean…

Analysis of PDEs · Mathematics 2025-04-18 Filomena Pacella , Giulio Tralli

We study the connection between amenability, F{\o}lner conditions and the geometry of finitely generated semigroups. Using results of Klawe, we show that within an extremely broad class of semigroups (encompassing all groups, left…

Group Theory · Mathematics 2015-05-25 Robert D. Gray , Mark Kambites

We study a group which is hyperbolic relative to a finite family of infinite subgroups. We show that the group satisfies the coarse Baum-Connes conjecture if each subgroup belonging to the family satisfies the coarse Baum-Connes conjecture…

K-Theory and Homology · Mathematics 2014-10-09 Tomohiro Fukaya , Shin-ichi Oguni

We construct compact hyperbolic 3-manifolds with totally geodesic boundary, such that the closed 3-pseudomanifolds obtained by coning off the boundary components are negatively curved and contain locally convex subspaces whose fundamental…

Geometric Topology · Mathematics 2026-02-11 Jason Manning , Lorenzo Ruffoni

In this paper we first extend from normed spaces to locally convex spaces some characterizations of denting points in convex sets. On the other hand, we also prove that in an infrabarreled locally convex space a point in a convex set is…

Functional Analysis · Mathematics 2024-01-17 Fernando García-Castaño , M. A. Melguizo Padial , G. Parzanese

A topological group $G$ is extremely amenable if every continuous action of $G$ on a compact space has a fixed point. Using the concentration of measure techniques developed by Gromov and Milman, we prove that the group of automorphisms of…

Group Theory · Mathematics 2007-09-03 Thierry Giordano , Vladimir Pestov

The generalized Lax conjecture asserts that each hyperbolicity cone is a linear slice of the cone of positive semidefinite matrices. We prove the conjecture for a multivariate generalization of the matching polynomial. This is further…

Combinatorics · Mathematics 2016-11-21 Nima Amini

We show that certain graphs of groups with cyclic edge groups are aTmenable. In particular, this holds when each vertex group is either virtually special or acts properly and semisimply on $\mathbb{H}^n$.

Group Theory · Mathematics 2017-01-03 Mathieu Carette , Daniel T. Wise , Daniel J. Woodhouse

Almost forty years ago, Connes, Feldman and Weiss proved that for measurable equivalence relations the notions of amenability and hyperfiniteness coincide. In this paper we define the uniform version of amenability and hyperfiniteness for…

Dynamical Systems · Mathematics 2020-08-25 Gábor Elek

Learning graph representations via low-dimensional embeddings that preserve relevant network properties is an important class of problems in machine learning. We here present a novel method to embed directed acyclic graphs. Following prior…

Machine Learning · Computer Science 2018-06-08 Octavian-Eugen Ganea , Gary Bécigneul , Thomas Hofmann

Complete hyperbolicity of small Euclidean balls with respect to a C^1-smooth almost complex structure standard at origin is improved to give a complete hyperbolicity of strictly pseudoconvex domains. More precise (and lower) regularity…

Complex Variables · Mathematics 2007-05-23 S. Ivashkovich , J. -P. Rosay

Variational analysis presents a unified theory encompassing in particular both smoothness and convexity. In a Euclidean space, convex sets and smooth manifolds both have straightforward local geometry. However, in the most basic hybrid case…

Optimization and Control · Mathematics 2025-01-29 Adrian S. Lewis , Adriana Nicolae , Tonghua Tian

This paper is about integral zonotopes. It is proven that large zonotopes in a convex cone have a limit shape, meaning that, after suitable scaling, the overwhelming majority of the zonotopes are very close to a fixed convex set. Several…

Combinatorics · Mathematics 2018-04-12 Imre Bárány , Julien Bureaux , Ben Lund