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We show that in any Euclidean space, an arbitrary probability measure can be reconstructed explicitly by its geometric (or spatial) distribution function. The reconstruction takes the form of a (potentially fractional) linear PDE, where the…

Statistics Theory · Mathematics 2024-04-11 Dimitri Konen

This paper introduces a new metric and mean on the set of positive semidefinite matrices of fixed-rank. The proposed metric is derived from a well-chosen Riemannian quotient geometry that generalizes the reductive geometry of the positive…

Optimization and Control · Mathematics 2009-10-21 Silvere Bonnabel , Rodolphe Sepulchre

When graviton loops are taken into account, the background metric obtained as a solution to the one-loop corrected Einstein equations turns out to be gauge fixing dependent. Therefore it is of no physical relevance. Instead we consider a…

High Energy Physics - Theory · Physics 2014-11-18 Diego A. R. Dalvit , Francisco D. Mazzitelli

We study Riemannian nilmanifolds associated with graphs. We prove that such a nilmanifold is geodesic orbit if and only if it is naturally reductive if and only if its defining graph is the disjoint union of complete graphs and the…

Differential Geometry · Mathematics 2018-10-19 Y. Nikolayevsky

In spaces of nonpositive curvature the existence of isometrically embedded flat (hyper)planes is often granted by apparently weaker conditions on large scales. We show that some such results remain valid for metric spaces with non-unique…

Metric Geometry · Mathematics 2016-03-15 Dominic Descombes , Urs Lang

The theory of geodesic regression aims to find a geodesic curve which is an optimal fit to a given set of data. In this article we restrict ourselves to the Riemannian manifold of positive definite operators (matrices) on a Hilbert space of…

Mathematical Physics · Physics 2020-05-29 Frank Hansen

We study the completeness of light trajectories in certain spherically symmetric regular geometries found in Palatini theories of gravity threaded by non-linear (electromagnetic) fields, which makes their propagation to happen along…

General Relativity and Quantum Cosmology · Physics 2023-09-25 Merce Guerrero , Gonzalo J. Olmo , Diego Rubiera-Garcia

We establish a framework, namely, nuclear bounded Fr\'{e}chet manifolds endowed with Riemann-Finsler structures to study geodesic curves on certain infinite dimensional manifolds such as the manifold of Riemannian metrics on a closed…

Differential Geometry · Mathematics 2020-07-29 Kaveh Eftekharinasab , Valentyna Petrusenko

In this paper we investigate possible extensions of the idea of geodesic completeness in complex manifolds, following two directions: metrics are somewhere allowed not to be of maximum rank, or to have 'poles' somewhere else. Geodesics are…

Complex Variables · Mathematics 2007-05-23 Claudio Meneghini

A new geometrical definition of naturally reductive Finsler manifold using geodeic graph is proposed, with a possible generalization. Based on a construction from a recent paper by the authors, Finsler metrics based on naturally reductive…

Differential Geometry · Mathematics 2025-10-28 Teresa Arias-Marco , Zdenek Dusek

Given a geodesic inside a simply-connected, complete, non-positively curved Riemannian (NPCR) manifold M, we get an associated geodesic inside the asymptotic cone Cone(M). Under mild hypotheses, we show that if the latter is contained…

Differential Geometry · Mathematics 2008-01-24 S. Francaviglia , J. -F. Lafont

We propose a general convex optimization problem for computing regularized geodesic distances. We show that under mild conditions on the regularizer the problem is well posed. We propose three different regularizers and provide analytical…

Graphics · Computer Science 2023-05-23 Michal Edelstein , Nestor Guillen , Justin Solomon , Mirela Ben-Chen

The concept of sharpness has been successfully applied to traditional architectures like MLPs and CNNs to predict their generalization. For transformers, however, recent work reported weak correlation between flatness and generalization. We…

Machine Learning · Computer Science 2025-05-09 Marvin F. da Silva , Felix Dangel , Sageev Oore

Consider a smooth manifold $M$ equipped with a bracket generating distribution $D$. Two sub-Riemannian metrics on $(M,D)$ are said to be projectively (resp. affinely) equivalent if they have the same geodesics up to reparameterization…

Differential Geometry · Mathematics 2019-03-04 F. Jean , S. Maslovskaya , I. Zelenko

Random geometric graphs are random graph models defined on metric spaces. Such a model is defined by first sampling points from a metric space and then connecting each pair of sampled points with probability that depends on their distance,…

Machine Learning · Computer Science 2026-04-10 Han Huang , Pakawut Jiradilok , Elchanan Mossel

We propose a new strong Riemannian metric on the manifold of (parametrized) embedded curves of regularity $H^s$, $s\in(3/2,2)$. We highlight its close relationship to the (generalized) tangent-point energies and employ it to show that this…

Differential Geometry · Mathematics 2025-12-17 Elias Döhrer , Philipp Reiter , Henrik Schumacher

Let $V$ be a separable Hilbert space, possibly infinite dimensional. Let $\St(p,V)$ be the Stiefel manifold of orthonormal frames of $p$ vectors in $V$, and let $\Gr(p,V)$ be the Grassmann manifold of $p$ dimensional subspaces of $V$. We…

Differential Geometry · Mathematics 2018-09-28 Philipp Harms , Andrea C. G. Mennucci

We define the notion of near geodesic between points of a metric space when no geodesic exists, and use this to extend Recio-Mitter's notion of geodesic complexity to non-geodesic spaces. This has potential application to topological…

Metric Geometry · Mathematics 2021-05-31 Donald M. Davis

Given a compact manifold with boundary with unknown Riemannian metric. The problem is to reconstruct the metric in a class of conformal metrics from knowledge of lengths of all closed geodesics (kinematic data). An integral inequality is…

Differential Geometry · Mathematics 2012-06-05 Victor Palamodov

Two curves are affinely equivalent if there exists an affine mapping transforming one of them onto the other. Thus, detecting affine equivalence comprises, as important particular cases, similarity, congruence and symmetry detection. In…

Algebraic Geometry · Mathematics 2024-03-27 Juan Gerardo Alcázar , Hüsnü Anıl Çoban , Uğur Gözütok