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In a recent paper, we gave a topological description of Colombeau type algebras introducing algebras of sequences with exponential weights. Embeddings of Schwartz' spaces into the Colombeau algebra G are well known, but for…

Functional Analysis · Mathematics 2007-05-23 Antoine Delcroix , Maximilian F. Hasler , Stevan Pilipović , Vincent Valmorin

In this paper, we study non integrable distributions in a Riemannian manifold with a semi-symmetric metric connection, a semi-symmetric non-metric connection and a statistical connection. We obtain the Gauss, Codazzi, and Ricci equations…

Differential Geometry · Mathematics 2019-10-18 Yong Wang

We establish a regularity result for the metric on any 4-dimensional extremal K\"ahler manifold, and a weak compactness theorem on the space of such metrics. Specifically, the sectional curvature at a point is bounded when the quantity…

Differential Geometry · Mathematics 2011-05-11 Brian Weber

The coordinate invariant theory of generalised functions of Colombeau and Meril is reviewed and extended to enable the construction of multi-index generalised tensor functions whose transformation laws coincide with their counterparts in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. A. Vickers , J. P. Wilson

The goal of this note is to show how recent results on the theory of quasi-stationary distributions allow to deduce effortlessly general criteria for the geometric convergence of normalized unbounded semigroups.

Probability · Mathematics 2021-02-19 Nicolas Champagnat , Denis Villemonais

We construct an algebra of generalized functions endowed with a canonical embedding of the space of Schwartz distributions. We offer a solution to the problem of multiplication of Schwartz distributions similar to but different from…

Functional Analysis · Mathematics 2008-10-08 Todor D. Todorov , Hans Vernaeve

We initiate the rigorous study of classification in semimetric spaces, which are point sets with a distance function that is non-negative and symmetric, but need not satisfy the triangle inequality. For metric spaces, the doubling dimension…

Machine Learning · Computer Science 2015-02-24 Lee-Ad Gottlieb , Aryeh Kontorovich

We show that the Riemannian Gaussian distributions on symmetric spaces, introduced in recent years, are of standard random matrix type. We exploit this to compute analytically marginals of the probability density functions. This can be done…

Mathematical Physics · Physics 2021-10-29 Leonardo Santilli , Miguel Tierz

We show that on every manifold, every conformal class of semi-Riemannian metrics contains a metric $g$ such that each $k$-th-order covariant derivative of the Riemann tensor of $g$ has bounded absolute value $a_k$. This result is new also…

Differential Geometry · Mathematics 2015-10-14 Olaf Müller , Marc Nardmann

We propose a new metric between probability measures on a compact metric space that mirrors the Riemannian manifold-like structure of quadratic optimal transport but includes entropic regularization. Its metric tensor is given by the…

Optimization and Control · Mathematics 2025-09-22 Hugo Lavenant , Jonas Luckhardt , Gilles Mordant , Bernhard Schmitzer , Luca Tamanini

We study existence, uniqueness, and distributional aspects of generalized solutions to the Cauchy problem for first-order symmetric (or Hermitian) hyperbolic systems of partial differential equations with Colombeau generalized functions as…

Analysis of PDEs · Mathematics 2011-11-10 Guenther Hoermann , Christian Spreitzer

We analyse the geometry of the rubber-rolling distribution on the special orthogonal group and show that almost all the normal geodesics of any right-invariant sub-Riemannian metric defined on this distribution are completely integrable.…

Differential Geometry · Mathematics 2025-08-19 Alejandro Bravo-Doddoli , Philip Arathoon , Anthony M. Bloch

We present a differential algebra of generalized functions over a field of generalized scalars by means of several axioms in terms of general algebra and topology. Our differential algebra is of Colombeau type in the sense that it contains…

Functional Analysis · Mathematics 2014-05-29 Todor D. Todorov

In spaces of metrics, we investigate topological distributions of the doubling property, the uniform disconnectedness, and the uniform perfectness, which are the quasi-symmetrically invariant properties appearing in the David--Semmes…

Metric Geometry · Mathematics 2021-05-12 Yoshito Ishiki

In this article we study limits of Wigner distributions (the so-called semiclassical measures) corresponding to sequences of solutions to the semiclassical Schroedinger equation at times scales $\alpha_{h}$ tending to infinity as the…

Analysis of PDEs · Mathematics 2009-04-06 Fabricio Macia

We prove that in metric measure spaces where the entropy functional is K-convex along every Wasserstein geodesic any optimal transport between two absolutely continuous measures with finite second moments lives on a non-branching set of…

Differential Geometry · Mathematics 2013-07-16 Tapio Rajala , Karl-Theodor Sturm

In this paper, a Riemannian geometry of noncommutative super surfaces is developed which generalizes [4] to the super case. The notions of metric and connections on such noncommutative super surfaces are introduced and it is shown that the…

Differential Geometry · Mathematics 2022-12-29 Yong Wang , Tong Wu

We present an extension of J. F. Colombeau's theory of nonlinear generalized functions to spaces of generalized sections of vector bundles. Our construction builds on classical functional analytic notions, which is the key to having a…

Functional Analysis · Mathematics 2016-02-19 Eduard A. Nigsch

In this paper non-asymptotic exact rearrangement invariant norm estimates are derived for the maximum distribution of the family elements of some rearrangement invariant (r.i.) space over unbounded measure in the entropy terms and in the…

Functional Analysis · Mathematics 2008-08-26 E. Ostrovsky , E. Rogover

We introduce a general framework for analyzing data modeled as parameterized families of networks. Building on a Gromov-Wasserstein variant of optimal transport, we define a family of parameterized Gromov-Wasserstein distances for comparing…

Machine Learning · Statistics 2025-09-29 Mario Gómez , Guanqun Ma , Tom Needham , Bei Wang