bio  website  regularize.wordpress.com 

location  Braunschweig, Germany  
age  36  
visits  member for  4 years 
seen  43 mins ago  
stats  profile views  1,705 
Professor at TU Braunschweig.
Area: Inverse problems, regularization theory, applied functional analysis, mathematical image processing.
5h

reviewed  Leave Closed Is the ISC kaput 
1d

reviewed  Close Zeromean assumptions concerning r.d.'s when reading graduatelevel probability texts 
1d

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. 
2d

reviewed  Close Blinding a paper : the acknowledgements section 
2d

reviewed  Leave Closed How did the summation operation come into use? 
2d

reviewed  Reopen Obscure Names in Mathematics 
2d

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 supnorm). 
2d

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 
reviewed  Close toledo's lecture on cartwirghtsteger surface 
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 
reviewed  Approve suggested edit on Which univariate function satisfies $e^{g(x)} + e^{g(x)} = \alpha x$ for $x>0$ and some constant $\alpha>0$? 
Oct 20 
answered  Quantitative stability: Hausdorff distance between subdifferentials 
Oct 17 
comment 
A fixed point problem about the iterated mappings
As the question appeared in the review queue, I started editing. Halfway through, I realized that the question does not make sense as stated… For what it's worth: The answers to your questions is: 1. $\lim f^m(x)$ does not exist (hence asking if it is in $\Omega$ or not does not make sense). 2. No. 3. See 1. 
Oct 17 
reviewed  Edit suggested edit on A fixed point problem about the iterated mappings 