6,807 reputation
22351
bio website fph.altervista.org
location Pisa, Italy
age 32
visits member for 5 years, 6 months
seen 8 hours ago

Numerical linear algebra. Mainly matrix equations and their applications (control theory, applied probability).

(This profile was written for Mathoverflow, but Stack Exchange insists on copying it over verbatim to other sites, where it makes less sense.)


19h
comment Eigenvectors as continuous functions of matrix - diagonal perturbations
What is constant and what is varying there? Is $D$ a matrix-valued function? Of how many parameters? How regular?
May
20
comment complexity of eigenvalue decomposition
Convergence of the unsymmetric QR algorithm is still an open problem. In the paper mentioned in my answer, the eigendecomposition is not computed using QR, but a completely different algorithm (inverse-free doubling).
May
20
revised complexity of eigenvalue decomposition
made complexity model clearer
May
20
awarded  Nice Answer
May
19
reviewed Approve Flat Riemannian manifold
May
16
reviewed Approve Gauss quadrature with weights
May
16
reviewed Approve isoperimetry tag wiki
May
16
reviewed Approve isoperimetry tag wiki excerpt
May
15
reviewed Approve holomorphic-symplectic tag wiki excerpt
May
8
comment Which operators other than self-adjoint operators have no purely imaginary eigenvalues?
For matrices, at least, there are other classes: M-matrices and Hurwitz stable matrices (which you can find, for instance, with Lyapunov stability criterion).
May
5
reviewed Approve Equation with $q$-binomial coefficients
May
4
reviewed Approve measure-theory tag wiki excerpt
May
3
reviewed Approve Coefficients of the pull-backs of divisors by resolving morphism
May
1
reviewed Approve Is there an introduction to probability theory from a structuralist/categorical perspective?
Apr
29
reviewed Approve Polynomials of low degree that clone polynomials of higher degree
Apr
29
reviewed Approve Atiyah's vector bundles over an elliptic curve
Apr
27
comment Is the set $ AA+A $ always at least as large as $ A+A $?
What is $AA$? $\{a^2 : a\in A\}$? Is it standard notation?
Apr
26
reviewed Approve A Question on 1, 2 ,3 Conjecture
Apr
26
reviewed Approve Source for roots of matrix polynomials?
Apr
21
reviewed Approve determinants tag wiki excerpt