3,037 reputation
1247
bio website regularize.wordpress.com
location Braunschweig, Germany
age 36
visits member for 4 years
seen 26 mins ago

Professor at TU Braunschweig.

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


Jun
5
revised How many facets can $\{\|D^T x\|_1\leq 1\}$ have?
Added an argument for the existence of $B$ and a guess for $n=2$.
Jun
4
comment Choice of MIP (mixed integer programming) solver
Probably you want to try out scicomp.stackexchange? I suspect that the question is a better fit over there...
May
29
comment Convergence of iterated stochastic matrices
Doesn't this answer a different question? I thought, the OP asked about the convergence of $\|M_n^n-M_n\|$ to zero...
May
27
comment Are norms intrinsically $\mathbb{R}$-valued?
I would say that norms are intrinsically $[0,\infty[$-valued.
May
27
comment Are norms intrinsically $\mathbb{R}$-valued?
What is a rig?$\mbox{}$
May
23
reviewed Approve suggested edit on Defining Multiplication in Polynomials over Rings of Matrices
May
22
reviewed Edit suggested edit on $(1+\epsilon)$-injective Banach spaces, complex scalars
May
22
revised $(1+\epsilon)$-injective Banach spaces, complex scalars
The reader should be warned first that the proof is wrong
May
21
reviewed Approve suggested edit on Exact formulas for the partition function?
May
16
comment Distance between probability amplitude functions
Reminds me a bit of the Hellinger distance (en.wikipedia.org/wiki/Hellinger_distance).
May
9
comment What is the oldest open problem in mathematics?
This is not a big-list question…
May
8
comment How many facets can $\{\|D^T x\|_1\leq 1\}$ have?
@CristóbalGuzmán Sure: both functionals are positively homogeneous, hence determined by their 1-levelset. Moreover, the set $\{\|D^Tx\|_1\leq 1\}$ is a centrally symmetric polytope, hence described by an intersection of finitely many half spaces, each of these appearing two times with opposite signs. Sets of this kind can be described as $\{\|B^Tx\|_\infty\leq 1\}$.
May
2
comment How to correct an error in a submitted paper?
"we're all human": If you speak of authors of mathematical paper then, technically, this is not true (math.rutgers.edu/~zeilberg/ekhad.html). Speaking of, e.g., MO users I am not sure either…
Apr
25
asked How many facets can $\{\|D^T x\|_1\leq 1\}$ have?
Apr
25
comment The Hidden Aspect of Set Theory
Regarding the reality of mathematical objects I found the chapter "Numbers and Abstraction" in Gowers' "Mathematics: A Very Short Introduction" eye opening. His point is basically: It is not of interest to mathematicians what some mathematical object is but what it does.
Apr
21
comment Inverse problem with a rank-1 update
I do not get what your tradeoffs are exactly... Also, what is a rank-one decomposition?
Apr
21
answered Distance between two networks
Apr
10
comment Why quintics are Calabi-Yau?
I find the question "Why quintics are Calabi-Yau" rather cryprtic. Would you mind to give some more information?
Apr
9
revised Determine noise distribution
edited tags
Apr
9
awarded  Revival