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We study metric-compatible Poisson structures in the semi-classical limit of noncommutative emergent gravity. Space-time is realized as quantized symplectic submanifold embedded in R^D, whose effective metric depends on the embedding as…

Mathematical Physics · Physics 2014-09-11 Nikolaj Kuntner , Harold Steinacker

We take a three dimensional Euclidian metric in toroidal coordinates and consider the corresponding Laplace equation. The simplest solution of this equation is taken. Based on this we build a Weyl space-time. This space-time is transformed…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. B. P. Wickramasuriya , V. Joseph , K. I. S. Karunaratne

We explicitly construct several Poisson structures with compact support. For example, we show that any Poisson structure on $\R^n$ with polynomial coefficients of degree at most two can be modified outside an open ball, such that it becomes…

Symplectic Geometry · Mathematics 2022-10-21 Gil R. Cavalcanti , Ioan Marcut

We formalize the notion of limit of an inverse system of metric spaces with $1$-Lipschitz projections having unbounded fibers. The purpose is to use sub-Riemannian groups for metrizing the space of signatures of rectifiable paths in…

Metric Geometry · Mathematics 2019-10-11 Enrico Le Donne , Roger Züst

Convex geometries are closure systems satisfying the anti-exchange axiom. Every finite convex geometry can be embedded into a convex geometry of finitely many points in an n-dimensional space equipped with a convex hull operator, by the…

Combinatorics · Mathematics 2016-09-02 Kira Adaricheva , Madina Bolat

We conjecture that a convex polytope is uniquely determined up to isometry by its edge-graph, edge lengths and the collection of distances of its vertices to some arbitrary interior point, across all dimensions and all combinatorial types.…

Combinatorics · Mathematics 2024-01-09 Martin Winter

We characterize strongly Morse quasi-geodesics in Outer space as quasi-geodesics which project to quasi-geodesics in the free factor graph. We define convex cocompact subgroups of $Out(F_n)$ as subgroups such that an orbit map in the free…

Geometric Topology · Mathematics 2017-03-21 Ursula Hamenstädt , Sebastian Hensel

This paper investigates a generalized hyperbolic circle packing (including circles, horocycles or hypercycles) with respect to the total geodesic curvatures on the surface with boundary. We mainly focus on the existence and rigidity of…

Geometric Topology · Mathematics 2023-11-20 Guangming Hu , Yi Qi , Yu Sun , Puchun Zhou

We study metric properties of manifolds with conic singularities and present a natural interplay between metrically conic and metrically asymptotically conic behaviour. As a consequence, we prove that a singular sub-manifold is Lipschitz…

Metric Geometry · Mathematics 2024-10-10 André Costa , Vincent Grandjean , Maria Michalska

There are several solutions of Einstein field equations that describe an inhomogeneity in an expanding universe. Among these solutions, the McVittie metric and its generalizations have been investigated through decades, though a full…

General Relativity and Quantum Cosmology · Physics 2019-01-29 Daniela Pérez , Gustavo E. Romero , Luciano E. Combi , Eduardo Gutiérrez

The paper is devoted to the study of geodesic orbit Riemannian spaces that could be characterize by the property that any geodesic is an orbit of a 1-parameter group of isometries. The main result is the classification of compact simply…

Differential Geometry · Mathematics 2020-05-19 Zhiqi Chen , Yu. G. Nikonorov

A basic representation of any real molecule is a finite cloud of unordered atoms, many of which are chemically indistinguishable. A natural equivalence on point clouds in any metric space is defined by isometries that are…

Metric Geometry · Mathematics 2026-04-07 Vitaliy Kurlin

Our work explores fusions, the multidimensional counterparts of mean-preserving contractions and their extreme and exposed points. We reveal an elegant geometric/combinatorial structure for these objects. Of particular note is the…

Theoretical Economics · Economics 2025-02-11 Andreas Kleiner , Benny Moldovanu , Philipp Strack , Mark Whitmeyer

The space of shapes of a polyhedron with given total angles less than 2\pi at each of its n vertices has a Kaehler metric, locally isometric to complex hyperbolic space CH^{n-3}. The metric is not complete: collisions between vertices take…

Geometric Topology · Mathematics 2007-05-23 William P. Thurston

In this paper we use a diffeo-geometric framework based on manifolds that are locally modeled on "convenient" vector spaces to study the geometry of some infinite dimensional spaces. Given a finite dimensional symplectic manifold…

Differential Geometry · Mathematics 2009-11-03 Brian Lee

Extra-terrestrial polymers of glycine with iron have been characterized by mass spectrometry to have a core mass of 1494Da with dominant rod-like variants at m/z 1567 and m/z 1639 [1]. Several principal macro-structural morphologies are…

Soft Condensed Matter · Physics 2021-07-21 Julie E. M. McGeoch , Malcolm W. McGeoch

Two-dimensional almost-Riemannian structures are generalized Riemannian structures on surfaces for which a local orthonormal frame is given by a Lie bracket generating pair of vector fields that can become collinear. We consider the…

Optimization and Control · Mathematics 2014-01-06 Ugo Boscain , Grégoire Charlot , Roberta Ghezzi , Mario Sigalotti

Polygon spaces have been studied extensively, and yet missing from the literature is a simple property that every polygon has: dimension. This is distinct (possibly) from the dimension of the ambient space in which the polygon lives. A…

General Topology · Mathematics 2020-09-17 Jack Love

We introduce and explore a new concept of evasive subspace with respect to a collection of subspaces sharing a common dimension, most notably partial spreads. We show that this concept generalises known notions of subspace scatteredness and…

Combinatorics · Mathematics 2023-10-17 Anina Gruica , Alberto Ravagnani , John Sheekey , Ferdinando Zullo

The notion of partial geodesic was introduced by Jamshidpey et al. in "Sets of medians in the non-geodesic pseudometric space of unsigned genomes with breakpoints", 2014. In this paper, we study the density of points on non-trivial partial…

Combinatorics · Mathematics 2018-01-16 Poly H. da Silva , Arash Jamshidpey , David Sankoff