18 citations · 38 across the 8 of their papers we have counts for
5 papers · 1 filter
Spectral gap estimates for some block matrices
Ivan Veselic, Kresimir Veselic
We estimate the size of the spectral gap at zero for some Hermitian block matrices. Included are quasi-definite matrices, quasi-semidefinite matrices (the closure of the set of the…
The TAN Theorem for Indefinite Quadratic Forms
Luka Grubišić, Vadim Kostrykin, Konstantin A. Makarov +1
A version of the Davis-Kahan Tan theorem [SIAM J. Numer. Anal. \textbf{7} (1970), 1 -- 46] for not necessarily semibounded linear operators defined by quadratic forms is prove…
Spectral perturbation bounds for selfadjoint operators
K. Veselic
We give general spectral and eigenvalue perturbation bounds for a selfadjoint operator perturbed in the sense of the pseudo-Friedrichs extension. We also give several generalisatio…
On weakly formulated Sylvester equations and applications
Luka Grubisic, Kresimir Veselic
We use a ``weakly formulated'' Sylvester equation to obtain new bounds for the rotation of spectral subspaces of a nonnegative selfadjoint o…
Energy Decay of Damped Systems
Krešimir Veselić
We present a new and simple bound for the exponential decay of second order systems using the spectral shift. This result is applied to finite matrices as well as to partial differ…