3,184 reputation
1348
bio website regularize.wordpress.com
location Braunschweig, Germany
age 36
visits member for 4 years, 2 months
seen 10 hours ago

Professor at TU Braunschweig.

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


Oct
29
comment Central-Slice-Theorem Analogue for Wavelet Transforms?
Why do you think that such analog should exist? The 2D Fourier transform and the 2D wavelet transform are not really similar things. You are aware of the fact that the wavelet transform results in a function that lives on a different set, right? Meanwhile, you may be interested in the ridgelet transform which combines the Radon and the wavelet transform.
Oct
29
awarded  Custodian
Oct
27
comment Anti-bidiagonal matrix with main anti-diagonal {1,2,3,…} and first sub-anti-diagonal {-1,-2,-3,…} has eigenvalues lambda={1,-2,3,-4,…}
Have you looked at the eigenvectors?
Oct
24
reviewed Leave Closed Is the ISC kaput
Oct
23
comment Are there examples of families of objects which are canonically isomorphic, but where diagrams of canonical isomorphisms don't commute?
In the first paragraph I thought that the unit square would be $[0,1]^2$ but then I realized that you had $[-1,1]^2$ in mind.
Oct
22
reviewed Close Blinding a paper : the acknowledgements section
Oct
22
reviewed Leave Closed How did the summation operation come into use?
Oct
22
reviewed Reopen Obscure Names in Mathematics
Oct
21
comment What should be considered a finite size of an infinite dimensional space?
I second Yemon's comment. You may note that in Yemon's example the natural inverse is not continuous if you equip both spaces with the natural norm of the larger space (i. e. the sup-norm).
Oct
21
comment What should be considered a finite size of an infinite dimensional space?
My naive way of looking at this kind of problems would be to take "natural topologies" on both sets and say one is smaller than the other if one can identify the objects the small space in a natural way with the objects in the larger space and this identification is continuous. So in Yemon's example, $B$ would be indeed smaller than $A$…
Oct
21
comment Integrals involving trigonometric functions and polynomes
Now I notice the question mark behind the formula. Maybe it's just a nitpick, but "Specify all…?" does not sound like a question to me (in contrast to "What are all…?"). Generalization per se may be a motivation but I thought you something more that this, e.g. that some integrals of this type appeared somewhere else.
Oct
21
awarded  Custodian
Oct
21
comment Integrals involving trigonometric functions and polynomes
I think that this would get a better response if it would come as a question and not a command and also accompanied by some motivation and more background.
Oct
21
comment Quantitative stability: Hausdorff distance between subdifferentials
@RobertIsrael Right, it's indeed simple. Well, this simply reflects that uniform convergence does not imply convergence of the derivative (although, in principle convexity could change things but apparently it doesn't).
Oct
20
comment Quantitative stability: Hausdorff distance between subdifferentials
Don't know of anything, but have you checked Rockafellar and Wets' "Variational Analysis"? By the way, I suspect that the situation could be different for smooth $f$ and $g$…
Oct
20
awarded  Custodian
Oct
20
reviewed Leave Closed A metric on $S^{2}$
Oct
20
answered Quantitative stability: Hausdorff distance between subdifferentials
Oct
15
comment Inverse Function Theorem on Zygmund Spaces, is the inverse in the same Zygmund Space?
What I mean is that you should post the same question here and at math.stackexchange simultaneously. This produces unrelated threads and wasted time of the community, see here.
Oct
15
comment Inverse Function Theorem on Zygmund Spaces, is the inverse in the same Zygmund Space?
Please do not cross-post the same question.