68 citations · 340 across the 26 of their papers we have counts for
8 papers · 1 filter
Parametrices and exact paralinearisation of semi-linear boundary problems
Jon Johnsen
The subject is parametrices for semi-linear problems, based on parametrices for linear boundary problems and on non-linearities that decompose into solution-dependent linear operat…
Simple proofs of nowhere-differentiability for Weierstrass's function and cases of slow growth
Jon Johnsen
Using a few basics from integration theory, a short proof of nowhere-differentiability of Weierstrass functions is given. Restated in terms of the Fourier transformation, the metho…
On the Theory of Type 1,1-Operators
Jon Johnsen
This dissertation concerns the pseudo-differential operators of type 1,1. These have been known especially since around 1980, when it was shown that they play an important role in…
-Theory of Type -Operators
Jon Johnsen
This is a continuation of recent work on the general definition of pseudo-differential operators of type , in Hörmander's sense. Continuity in -Sobolev spaces and Hölder-…
Pointwise estimates of pseudo-differential operators
Jon Johnsen
As a new technique it is shown how general pseudo-differential operators can be estimated at arbitrary points in Euclidean space when acting on functions with compact spectra.…
Characterisation by Local Means of Anisotropic Lizorkin--Triebel Spaces with Mixed Norms
Jon Johnsen, Sabrina Munch Hansen, Winfried Sickel
This is a contribution to the theory of Lizorkin--Triebel spaces having mixed Lebesgue norms and quasi-homogeneous smoothness. We discuss their characterisation in terms of general…