Britta
  • Member for 2 years, 1 month
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1 answers
5 votes
130 views
What does the Kalman filter generally converge to? And why?
1 answers
2 votes
35 views
How can i rewrite my specific $F_{n,2d}^a$ polynomial to be a sum of $(3n-4)$ squares?
1 answers
2 votes
75 views
1 bookmarks
How to prove Fekete / Markov-Lukasz theorem: nonnegative univariate polynomial on [-1,1] can be decomposed accoording to even/odd-ness of degree
1 answers
2 votes
139 views
1 bookmarks
Prove that $X$ is PSD $\iff$ the principal submatrix of $X$ with all maximally linearly independent columns (and corresponding rows) left is PD.
0 answers
1 votes
25 views
How to calculate $\max\{\frac{1}{2}\sum_{i=1}^5(1-X_{i,i+1}) \mid X \text{ PSD}, X_{ii}=1 \forall i\in [5]\}$ analytically.
0 answers
1 votes
27 views
What does edge-transitive imply for the adjacency matrix of graph?
1 answers
1 votes
81 views
Why is the minimum rank of a matrix that fits a graph G larger or equal to the cardinality of the maximum stable set.
0 answers
1 votes
66 views
Why is the theta number / Lovasz number additive on disjoint graphs?
0 answers
1 votes
31 views
How to rewrite the intersection of two hyperplanes
0 answers
1 votes
174 views
What can we say about the product of minors of a symmetric matrix?
1 answers
1 votes
34 views
Why are there $\binom{2k+n-1}{2k}$ ways to create a homogeneous polynomial term of degree $2k$ with $n$ variables?
0 answers
1 votes
32 views
What are some basic methods to solve a recursive function of the shape $f_n = \alpha f_{n-1} + \beta f_{n-2}$ where $\alpha, \beta \in\mathbb{R}$
0 answers
0 votes
21 views
How to prove the set $ K=\{X\in S^n_+ | <A,X>=a, <B,X>=b, <C,X>=c\}$ is a bounded set, when there exist $e,f,k\in\mathbb{R}$ st $e A+f B+k C$ PSD
0 answers
0 votes
41 views
How do I show that for an open, nonempty subset $A$ of a topological vector space $V$ is convex?
1 answers
0 votes
56 views
Show that, if $A$ is PSD, then there is an optimal solution $x_i, y_j$ of the below given optimization problem such that $x_i = y_i$ for all $i$
1 answers
0 votes
23 views
1 bookmarks
Why is the smallest dimension for which there exists an orthogonal representation bounded by the coloring of the complement?
1 answers
0 votes
46 views
For full-dimensional cone $K$, $x\in int(K)$, can you take arb. vector $y$ and for some $t$ small enough have that $x-ty\in int(K)$
2 answers
0 votes
55 views
Can we rewrite $\prod \frac{e^{y_i}}{y_i}$ in any way?
1 answers
0 votes
147 views
Given a closed, convex, full-dimensional cone $K$, how do I show that $u\in int(K) \iff u^tx>0 \quad \forall x\in K^*-\{0\}$?
1 answers
0 votes
23 views
Why is a matrix $Z = (<u_iu_i^T,u_ju_j^T>)_{i,j\in [n+1]}$ with $\{u_i\}_{i\in[n]}$ orthonormal representation of a graph positive semi-definite?
1 answers
0 votes
43 views
When applying semidefinite optimization to sum of squares polynomials, why do you want the determinant of you polynomial matrix to be non-negative?
2 answers
0 votes
121 views
1 bookmarks
How to prove the $n\times n$ matrix $A=\big(\frac{1}{i+j+1}\big)_{i,j\in [n]}$ is positive semi-definite?
0 answers
0 votes
28 views
What is the concept behind this 'dual problem'?