3,553 reputation
12051
bio website regularize.wordpress.com
location Braunschweig, Germany
age 36
visits member for 4 years, 10 months
seen 2 days ago

Professor at TU Braunschweig.

Area: Inverse problems, regularization theory, applied functional analysis, mathematical image processing.


Nov
24
comment fixed point arguments in PDE
Would Schauder's fixed point theorem be standard or advanced?
Nov
14
comment Why is the Gaussian so pervasive in mathematics?
Isn't this connection the reason why the Gaussian is called Gaussian? If I remember correctly, Gauss introduced "least squares" as a regression technique not because its derivative gives rise to a linear problem but because the square fits the "normal error model", i.e. corresponds to the Gaussian distribution.
Nov
13
comment Weak convergence of the image of a weakly $L^1$ converging sequence
Not an answer, but I vaguely recall that the only functions $f$ for which $u_k$ weakly to $u$ implies $f(u_k)$ weakly to $f(u)$ are affine linear $f$'s.
Nov
5
awarded  Nice Answer
Nov
1
answered A sudden smiley? :-)
Oct
22
awarded  Popular Question
Oct
20
comment Inversion of Radon transform by incomplete data: specific case
Could you expand on the relation of the Radon transform and economics? (Out of curiosity.)
Oct
19
comment What software one needs to solve a big linear system on a small computer?
I also recommend octave. 10000 x 10000 is doable, although the matrix needs 800MB (if not sparse). On my laptop it takes about a minute to solve a system like this.
Oct
16
comment Measuring almost-critical values of smooth functions.
Did you inspect the one-dimensional case $X=\mathbb{R}$? I suspect that basically arbitrary functions $M_f$ are possible.
Oct
15
comment Terminology for notion dual to “support”
I don't know if this point is important, but usually, the support of $f$ is the closure of the set on which $f$ is non-zero (assuming some topology on the domain of $f$).
Oct
15
revised Convex Combination of 2 hermitian matrices
made matrices indefinite
Oct
15
comment Convex Combination of 2 hermitian matrices
Oh yes - why not...
Oct
15
answered Convex Combination of 2 hermitian matrices
Oct
10
comment When should I publish my results?
This question could also have been asked at academia.stackexchange.com
Oct
3
comment sequences of plane measures converging to a singular one: terminology, etc
Correct. BY the way: The former ones (uniform measures on "full" triangles) are absolutely continuous w.r.t. Lebesgue measure. Probably also Lebesgue's decomposition theorem (en.wikipedia.org/wiki/Lebesgue%27s_decomposition_theorem) could be helpful.
Oct
3
answered sequences of plane measures converging to a singular one: terminology, etc
Sep
29
awarded  Yearling
Sep
13
answered Log-nonexpansive functions: terminology and references
Sep
10
comment Linear system of equations with nonnegative solutions and a recursion rule
OEIS (oeis.org) does not know both sequences...
Aug
30
comment How should an analytic number theorist look at Bessel functions?
Isn't there some $f$ missing in the formula for $\hat f$?