25 citations · 40 across the 9 of their papers we have counts for
9 papers
Ultradifferentiable regularity properties of a class of hypoelliptic operators
Stefan Fürdös
We investigate the ultradifferentiable regularity of solutions and vectors of a class of hypoelliptic differential operators first introduced by Hörmander. Our results extend resul…
Sheaves of ultradifferentiable functions
Stefan Fürdös
An abstract theory of ultradifferentiable sheaves is developed. Moreover, various applications to the theory of linear partial differential equations, differential geometry and, in…
Hypoellipticity of analytic differential operators in general ultradifferentiable classes
Stefan Fürdös
We show that analytic pseudodifferential and Fourier integral operators behave well for ultradifferentiable classes satisfying minimal regularity properties. As an application we i…
The Metivier inequality and ultradifferentiable hypoellipticity
Paulo D. Cordaro, Stefan Fürdös
In 1980 M{é}tivier characterized the analytic (and Gevrey) hypoellipticity of -solvable partial linear differential operators by a-priori estimates. In this note we extend thi…
Ellipticity and the problem of iterates in Denjoy-Carleman classes
Stefan Fürdös, Gerhard Schindl
In 1978 Métivier showed that a differential operator with analytic coefficients is elliptic if and only if the theorem of iterates holds for with respect to any non-analyti…
The Kotake-Narasimhan Theorem in general ultradifferentiable classes
Stefan Fürdös
We prove a Kotake-Narasimhan type theorem in general ultradifferentiable classes given by weight matrices. In doing so we simultaneously recover and partially generalize the known…
The Theorem of Iterates for elliptic and non-elliptic Operators
Stefan Fürdös, Gerhard Schindl
We introduce a new approach for the study of the Problem of Iterates using the theory on general ultradifferentiable structures developed in the last years. Our framework generaliz…
Almost analytic extensions of ultradifferentiable functions with applications to microlocal analysis
Stefan Fürdös, David Nicolas Nenning, Armin Rainer +1
We review and extend the description of ultradifferentiable functions by their almost analytic extensions, i.e., extensions to the complex domain with specific vanishing rate of th…
Regularity of infinitesimal CR automorphisms
Stefan Fürdös, Bernhard Lamel
We study the regularity of infinitesimal CR automorphisms of abstract CR structures which possess a certain microlocal extension and show that there are smooth multipliers, complet…