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Related papers: On the Geroch-Traschen class of metrics

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Two pseudo-Riemannian metrics $g $ and $\bar g$ are geodesically equivalent, if they share the same (unparameterized) geodesics. We give a complete local description of such metrics which solves the natural generalisation of Beltrami…

Differential Geometry · Mathematics 2017-11-30 Alexey V. Bolsinov , Vladimir S. Matveev

In this note we prove that the Heisenberg group with a left-invariant pseudo-Riemannian metric admits a completely integrable totally geodesic distribution of codimension 1. This is on the contrary to the Riemannian case, as it was proved…

Differential Geometry · Mathematics 2010-03-02 Wafaa Batat , Salima Rahmani

We introduce a class of metrics on $\mathbb{R}^n$ generalizing the classical Grushin plane. These are length metrics defined by the line element $ds = d_E(\cdot,Y)^{-\beta}ds_E$ for a closed nonempty subset $Y \subset \mathbb{R}^n$ and…

Metric Geometry · Mathematics 2021-12-20 Matthew Romney

We characterize non-reflexive Banach spaces by a low-distortion (resp. isometric) embeddability of a certain metric graph up to a renorming. Also we study non-linear sufficient conditions for $\ell_1^n$ being $(1+\varepsilon)$-isomorphic to…

Functional Analysis · Mathematics 2016-07-29 Antonin Prochazka

Within a framework of noncommutative geometry, we develop an analogue of (pseudo) Riemannian geometry on finite and discrete sets. On a finite set, there is a counterpart of the continuum metric tensor with a simple geometric…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. Dimakis , F. Muller-Hoissen

For a metrizable space $X$, we denote by $\mathrm{Met}(X)$ the space of all metric that generate the same topology of $X$. The space $\mathrm{Met}(X)$ is equipped with the supremum distance. In this paper, for every strongly…

Metric Geometry · Mathematics 2023-04-20 Yoshito Ishiki

The space of all non degenerate bilinear structures on a manifold $M$ carries a one parameter family of pseudo Riemannian metrics. We determine the geodesic equation, covariant derivative, curvature, and we solve the geodesic equation…

Differential Geometry · Mathematics 2016-09-06 Olga Gil-Medrano , Peter W. Michor , Martin Neuwirther

In this article, we first provide a survey of pressure metrics on various deformation spaces in geometry, topology, and dynamics. Then we discuss pressure semi-norms and their degeneracy loci in the space of quasi-Blaschke products

Dynamical Systems · Mathematics 2025-01-30 Yan Mary He , Homin Lee , Insung Park

We establish elliptic regularity for nonlinear inhomogeneous Cauchy-Riemann equations under minimal assumptions, and give a counterexample in a borderline case. In some cases where the inhomogeneous term has a separable factorization, the…

Complex Variables · Mathematics 2015-10-05 Adam Coffman , Yifei Pan , Yuan Zhang

We use moving frame techniques to derive a notion of curvature for a class of piecewise-smooth Riemannian metrics called Regge metrics, showing that it is a measure that simultaneously satisfies the (weak) Cartan structure equations and the…

Differential Geometry · Mathematics 2026-02-03 Evan S. Gawlik , Jack McKee

A fundamental result of thermodynamic geometry is that the optimal, minimal-work protocol that drives a nonequilibrium system between two thermodynamic states in the slow-driving limit is given by a geodesic of the friction tensor, a…

Statistical Mechanics · Physics 2024-10-24 Adrianne Zhong , Michael R. DeWeese

In previous work the authors defined the k-th order simplicial distance between probability distributions which arises naturally from a measure of dispersion based on the squared volume of random simplices of dimension k. This theory is…

Statistics Theory · Mathematics 2018-09-06 Luc Pronzato , Henry Wynn , Anatoly Zhigljavsky

We prove a central limit theorem (CLT) for the Frechet mean of independent and identically distributed observations in a compact Riemannian manifold assuming that the population Frechet mean is unique. Previous general CLT results in this…

Probability · Mathematics 2022-11-01 Thomas Hotz , Huiling Le , Andrew T. A. Wood

Identifiability of statistical models is a fundamental and essential condition that is required to prove the consistency of maximum likelihood estimators. The identifiability of the skew families of distributions on the circle and cylinder…

Statistics Theory · Mathematics 2022-04-05 Yoichi Miyata , Takayuki Shiohama , Toshihiro Abe

We consider a class of abstract quasilinear parabolic problems with lower--order terms exhibiting a prescribed singular structure. We prove well--posedness and Lipschitz continuity of associated semiflows. Moreover, we investigate global…

Analysis of PDEs · Mathematics 2018-08-06 Jeremy LeCrone , Gieri Simonett

In this communication, the derivation of the Boltzmann-Gibbs and the Maxwellian distributions is presented from a geometrical point of view under the hypothesis of equiprobability. It is shown that both distributions can be obtained by…

Chaotic Dynamics · Physics 2010-01-20 Ricardo Lopez-Ruiz , Jaime Sanudo , Xavier Calbet

Score-based Generative Models (SGMs) approximate a data distribution by perturbing it with Gaussian noise and subsequently denoising it via a learned reverse diffusion process. These models excel at modeling complex data distributions and…

Machine Learning · Computer Science 2025-09-23 Stefano Bruno , Sotirios Sabanis

Phenomena with a constrained sample space appear frequently in practice. This is the case e.g. with strictly positive data and with compositional data, like percentages and the like. If the natural measure of difference is not the absolute…

Methodology · Statistics 2008-02-20 G. Mateu-Figueras , V. Pawlowsky-Glahn , J. J. Egozcue

q-Gaussian distribution appear in many science areas where we can find systems that could be described within a nonextensive framework. Usually, a way to assert that these systems belongs to nonextensive framework is by means of numerical…

Data Analysis, Statistics and Probability · Physics 2017-03-21 Wagner S. de Lima , Emerson L. de Santa Helena

A consistent generalization of statistical mechanics is obtained by applying the maximum entropy principle to a trace-form entropy and by requiring that physically motivated mathematical properties are preserved. The emerging…

Statistical Mechanics · Physics 2009-11-10 G. Kaniadakis , M. Lissia , A. M. Scarfone