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20052025
most citedInternal sets and internal functions in Colombeau theory

42 citations · 107 across the 22 of their papers we have counts for

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22 papers · 1 filter

math.FA2025

Generalized functions with infinitesimals

Hans Vernaeve

We give a survey of the use of infinitesimals within mathematical analysis to rigorously deal with the delta-function from physics, and more generally, with distributions in the se…

math.FA2021

A Grothendieck topos of generalized functions I: basic theory

Paolo Giordano, Michael Kunzinger, Hans Vernaeve

The main aim of the present work is to arrive at a mathematical theory close to the historically original conception of generalized functions, i.e. set theoretical functions define…

math.FA2020

Filter-dependent versions of the Uniform Boundedness Principle

Ben De Bondt, Hans Vernaeve

For every filter on , we introduce and study corresponding uniform -boundedness principles for locally convex topological vector spaces. These p…

math.FA2017★ 3 cited

A non-linear theory of infrahyperfunctions

Andreas Debrouwere, Hans Vernaeve, Jasson Vindas

We develop a nonlinear theory for infrahyperfunctions (also referred to as quasianalytic (ultra)distributions by L. Hörmander). In the hyperfunction case our work can be summarized…

math.FA2016

Regularity of nonlinear generalized functions: a counterexample in the nonstandard setting

H. Vernaeve

Regularity theory in generalized function algebras of Colombeau type is largely based on the notion of -regularity, which reduces to -regularity when…

math.FA2016

An application of internal objects to microlocal analysis in generalized function algebras

Hans Vernaeve

We illustrate the use of internal objects in the nonlinear theory of generalized functions by means of an application to microlocal analysis in Colombeau algebras.

math.FA2016★ 15 cited

Optimal embeddings of ultradistributions into differential algebras

Andreas Debrouwere, Hans Vernaeve, Jasson Vindas

We construct embeddings of spaces of non-quasianalytic ultradistributions into differential algebras enjoying optimal properties in view of a Schwartz type impossibility result, al…

math.FA2015★ 2 cited

Microlocal analysis in generalized function algebras based on generalized points and generalized directions

Hans Vernaeve

We develop a refined theory of microlocal analysis in the algebra of Colombeau generalized functions. In our approach, the wave front is a set of generalized poin…

math.FA2014

Strongly internal sets and generalized smooth functions

Paolo Giordano, Michael Kunzinger, Hans Vernaeve

Based on a refinement of the notion of internal sets in Colombeau's theory, so-called strongly internal sets, we introduce the space of generalized smooth functions, a maximal exte…

math.FA2012★ 4 cited

Characterization of distributions having a value at a point in the sense of Robinson

Hans Vernaeve, Jasson Vindas

We characterize Schwartz distributions having a value at a single point in the sense introduced by means of nonstandard analysis by A. Robinson. They appear to be distributions con…

math.FA2011

Nonstandard principles for generalized functions

Hans Vernaeve

Someone knowledgeable in nonstandard analysis may get the feeling that in the nonlinear theory of generalized functions, too often one works directly on the nets and spends effort…

math.FA2010

Topological properties of regular generalized function algebras

Hans Vernaeve

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

math.FA2008★ 1 cited

Banach -algebras

Hans Vernaeve

We study Banach -algebras, i.e., complete ultra-pseudo-normed algebras over the ring of Colombeau generalized complex numbers. We dev…

math.FA2008★ 8 cited

Generalized analytic functions on generalized domains

Hans Vernaeve

We define the algebra of Colombeau generalized functions on a subset A of the space of d-dimensional generalized points. If the domain A is open, such generalized functions can be…

math.FA2007★ 13 cited

Pointwise characterizations in generalized function algebras

Hans Vernaeve

We define the algebra of Colombeau generalized functions on the space of generalized points of {\mathbb R}^d which naturally contains the tempered generalized functions. The subalg…

math.FA2007★ 1 cited

Full Algebra of Generalized Functions and Non-Standard Asymptotic Analysis

Todor D. Todorov, Hans Vernaeve

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…

math.FA2007★ 1 cited

Weak homogeneity in generalized function algebras

Hans Vernaeve

In this paper, weakly homogeneous generalized functions in the special Colombeau algebras are determined up to equality in the sense of generalized distributions. This yields chara…

math.FA2007★ 1 cited

Hilbert $\widetilde{\C}$-modules: structural properties and applications to variational problems

Claudia Garetto, Hans Vernaeve

We develop a theory of Hilbert $\widetilde{\C}$-modules by investigating their structural and functional analytic properties. Particular attention is given to finitely generated su…

math.FA2007★ 42 cited

Internal sets and internal functions in Colombeau theory

M. Oberguggenberger, H. Vernaeve

Inspired by nonstandard analysis, we define and study internal subsets and internal functions in algebras of Colombeau generalized functions. We prove a saturation principle for in…

math.FA2006★ 12 cited

Isomorphisms of algebras of Colombeau generalized functions

Hans Vernaeve

We show that for smooth manifolds X and Y, any isomorphism between the special algebra of Colombeau generalized functions on X, resp. Y is given by composition with a unique Colomb…

math.FA2005

The Local Structure of Nonstandard Representatives of Distributions

Hans Vernaeve

It is shown that the nonstandard representatives of Schwartz-distributions, as introduced by K.D. Stroyan and W.A.J. Luxemburg in their book 'Introduction to the theory of infinite…

math.FA2005★ 1 cited

Group invariant Colombeau generalized functions

Hans Vernaeve

Colombeau generalized functions invariant under smooth (additive) one-parameter groups are characterized. This characterization is applied to generalized functions invariant under…