English
Related papers

Related papers: A convenient notion of compact set for generalized…

200 papers

This paper lays the foundations for a nonlinear theory of differential geometry that is developed in a subsequent paper which is based on Colombeau algebras of tensor distributions on manifolds. We adopt a new approach and construct a…

Functional Analysis · Mathematics 2019-10-14 Eduard A. Nigsch , James A. Vickers

In this work, standard methods of the mixed thin-shell foramlism are refined using the framework of Colombeau's theory of generalized functions. To this end, systematic use is made of smooth generalized functions, in particular…

General Relativity and Quantum Cosmology · Physics 2025-05-07 Albert Huber

The Colombeau algebra of generalized functions allows to unrestrictedly carry out products of distributions. We analyze this operation from a microlocal point of view, deriving a general inclusion relation for wave front sets of products in…

Functional Analysis · Mathematics 2007-05-23 Guenther Hoermann , Michael Kunzinger

We define a general notion of set of indices which, using concepts from pre-ordered sets theory, permits to unify the presentation of several Colombeau-type algebras of nonlinear generalized functions. In every set of indices it is possible…

Functional Analysis · Mathematics 2014-08-07 Paolo Giordano , Eduard Nigsch

Co lombeau's construction of generalized functions (in its special variant) is extended to a theory of generalized sections of vector bundles. As particular cases, generalized tensor analysis and exterior algebra are studied. A point value…

Functional Analysis · Mathematics 2007-05-23 Michael Kunzinger , Roland Steinbauer

We study universal approximation of continuous functionals on compact subsets of products of Hilbert spaces. We prove that any such functional can be uniformly approximated by models that first take finitely many continuous linear…

Machine Learning · Computer Science 2026-02-04 Andrey Krylov , Maksim Penkin

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

Colombeau algebras constitute a convenient framework for performing nonlinear operations like multiplication on Schwartz distributions. Many variants and modifications of these algebras exist for various applications. We present a…

Functional Analysis · Mathematics 2013-07-02 E. A. Nigsch

The concept of generalized functions taking values in a differentiable manifold is extended to a functorial theory. We establish several characterization results which allow a global intrinsic formulation both of the theory of…

Functional Analysis · Mathematics 2007-05-23 Michael Kunzinger , Roland Steinbauer , James A. Vickers

We present some remarks about the embedding of spaces of Schwartz distributions into spaces of Colombeau generalized functions. We show that the various constructions of such embeddings existing in the literature lead in fact to the same…

Functional Analysis · Mathematics 2007-06-13 A. Delcroix

We present a comprehensive survey on removability of compact plane sets with respect to various classes of holomorphic functions. We also discuss some applications and several open questions, some of which are new.

Complex Variables · Mathematics 2015-12-17 Malik Younsi

The definition of a non-trivial space of generalized functions of a complex variable allowing to consider derivatives of continuous functions is a non-obvious task, e.g. because of Morera theorem, because distributional Cauchy-Riemann…

Functional Analysis · Mathematics 2025-10-30 Sekar Nugraheni , Paolo Giordano

Using the existence of infinite numbers $k$ in the non-Archimedean ring of Robinson-Colombeau, we define the hyperfinite Fourier transform (HFT) by considering integration extended to $[-k,k]^{n}$ instead of $(-\infty,\infty)^{n}$. In order…

Functional Analysis · Mathematics 2022-10-03 Akbarali Mukhammadiev , Diksha Tiwari , Paolo Giordano

We give an overview of the development of algebras of generalized functions in the sense of Colombeau and recent advances concerning diffeomorphism invariant global algebras of generalized functions and tensor fields. We furthermore provide…

Functional Analysis · Mathematics 2014-07-01 Eduard A. Nigsch , Clemens Sämann

We characterize microlocal regularity of Colombeau generalized functions by an appropriate extension of the classical notion of micro-ellipticity to pseudodifferential operators with slow scale generalized symbols. Thus we obtain an…

Analysis of PDEs · Mathematics 2007-05-23 Claudia Garetto , Guenther Hoermann

We investigate density of various subalgebras of regular generalized functions in the special Colombeau algebra of generalized functions.

Functional Analysis · Mathematics 2017-05-24 Hans Vernaeve

A new classification of real functions and other related real objects defined within a compact interval is proposed. The scope of the classification includes normal real functions and distributions in the sense of Schwartz, referred to…

Mathematical Physics · Physics 2015-07-07 Jorge L. deLyra

We study invariance properties of Colombeau generalized functions under actions of smooth Lie transformation groups. Several characterization results analogous to the smooth setting are derived and applications to generalized rotational…

Functional Analysis · Mathematics 2007-05-23 Sanja Konjik , Michael Kunzinger

We offer an axiomatic definition of a differential algebra of generalized functions over an algebraically closed non-Archimedean field. This algebra is of Colombeau type in the sense that it contains a copy of the space of Schwartz…

Functional Analysis · Mathematics 2015-03-18 Todor D. Todorov

We prove a compact embedding theorem in a class of spaces of piecewise H1 functions subordinated to a class of shape regular, but not necessarily quasi-uniform triangulations of a polygonal domain. This result generalizes the…

Numerical Analysis · Mathematics 2013-03-01 Sheng Zhang