All Questions
6 questions
7
votes
2
answers
507
views
What are the upper bound and stability conditions for the following simple linear system?
Consider the following linear system
$$\dot{x}=\sum\limits_{i=1}^{m}{{{\alpha }_{i}}}\left( t \right)\cdot {{A}_{i}}\cdot x \quad (1)
$$
where, $x\in {{\mathbb{R}}^{n}}$ represents the state vector, $...
4
votes
4
answers
3k
views
The multiplicity of the max eigenvalue in matrix multiplication
Suppose that eigenvalues of two real square matrix $A$ and $B$ are $1 = \lambda^A_1 > \lambda^A_2 \geq \ldots \geq \lambda^A_n > 0 $ and $1 = \lambda^B_1 > \lambda^B_2 \geq \ldots \geq \...
4
votes
0
answers
749
views
When the integral of the product of two matrix exponentials is singular?
Let $A$ and $B$ be two $n \times n$ real matrices. (In my application, $A$ and $B$ are $6\times 6$ traceless singular real matrices) I am interested in finding the smallest $T$ such that the integral $...
1
vote
1
answer
146
views
Solve a linear matrix ODE involving symmetric blocks
Let $P \in \mathbb R^{n \times n}$ be a symmetric positive definite matrix with eigenvalues denoted by $\lambda_i$ and corresponding eigenvectors denoted by $v_i$. For each $j \in \{1, 2, 3, 4\}$, let ...
1
vote
1
answer
167
views
Second order matrix differential equation in the space of symmetric positive definite matrices
In the construction of interpolations in the space of Gaussian measures, I encountered a second order matrix differential equation in the set of symmetric positive definite matrices $\mathbb{S}_+^d\...
1
vote
0
answers
496
views
Reverse-mode Hessian matrix of the Cholesky factor
Let $ f(L) $ be a scalar function of the lower triangular Cholesky decomposition of the covariance matrix $ \Sigma $ such as $ \Sigma = LL' $.
Let's assume that we know the first and second derivative ...