13,381 reputation
32574
bio website suvrit.de
location Internet
age
visits member for 4 years, 2 months
seen 2 mins ago

Researcher in Optimization, Machine Learning, etc.

Hobbyist in a small fraction of the world of Inequalities, Matrix Analysis, Noncommutative polynomials.

I'm here mostly to learn old and new mathematics!


8h
reviewed Close Parity of primes
8h
reviewed Close Obscure Names in Mathematics
1d
comment Comparing the inverse of a diagonally dominant matrix
If $A \preceq B$, then $A^{-1} \succeq B^{-1}$ as the inverse map is order reversing....
1d
comment Publishing in mathematics
The answer to your question, and all such fuzzy questions, is the usual: "it depends"
2d
comment Ratio sum comparison on operators
@WillJagy: finally this has been laid to rest :-)
2d
revised Ratio sum comparison on operators
added link to the solution by K. Audenaert!
2d
reviewed Close Mellin transform on $\mathbb{Z}[\omega]$
Oct
19
comment The complex heat kernel on a Riemann manifold
Here's a bunch of links: amazon.com/The-Mehler-Kernel-Erwin-Kronberger/dp/3639241193 $$\ \ \ $$ google.com/…
Oct
19
awarded  linear-algebra
Oct
19
comment Operator norm versus Hlawka inequality
So the question is whether this inequality holds for arbitrary $2\times 2$ matrices under the operator norm?
Oct
19
comment Is the notation ${}^t g$ for the transpose of a linear transformation intended to be suggestive?
@GeraldEdgar: I see, that's where it comes from!
Oct
18
answered Which nonnegative matrices have exact nonnegative matrix factors of smaller dimensionality?
Oct
18
comment Is the notation ${}^t g$ for the transpose of a linear transformation intended to be suggestive?
I guess to highlight that transposition itself is a linear operation, so it makes "pedantic" sense to have it appear before (though I find it grotesque, rather than "highbrow")...
Oct
17
comment How is constrained optimization done?
Wrong site for such a question, though given the breadth of possible answers, this question is not yet suitable for the other SE sites either (e.g., scicomp.SE, math.SE, etc.)
Oct
17
comment A lower bound on $\|\cdot\|_{p_{\ast}}$ image of $\ell^{q_{\ast}}$ vectors
Nice paper Cristóbal! I should read it!
Oct
17
reviewed Close quadratic knacksack problem, state of art
Oct
17
comment An inequality for the ratio of standard Young tableau with {1,2,…,k} in the first row
Somehow this reminds me of a related Schur polynomial majorization style inequality that once Gjergji Zaimi had posted on MO....cannot find that link right now..
Oct
17
comment Can we define log-convex operators?
One introduction to this for positive definite matrices (as a classical example) is to look at my paper: arxiv.org/abs/1312.1039 (the citations in that paper will lead you to more classical references for related material)
Oct
16
reviewed Close Population Variance PDF given Sample Variance
Oct
16
comment Can we define log-convex operators?
For starters, if you restrict to positive elements in your space, then this should be doable. Probably best to think in terms of convex cones with the associated partial order.