On nonnegative realization of partitioned spectra.
On nonnegative sign equivalent and sign similar factorizations of matrices.
On numerical range of sp(2n, C)
In this paper we studied the classical numerical range of matrices in sp(2n, C). We obtained some result on the relationship between the numerical range of a matrix in and that [...] of its diagonal block, the singular values of its off-diagonal block A2.
On pairs of matrices with property
On potentially nilpotent double star sign patterns
A matrix whose entries come from the set is called a sign pattern matrix, or sign pattern. A sign pattern is said to be potentially nilpotent if it has a nilpotent realization. In this paper, the characterization problem for some potentially nilpotent double star sign patterns is discussed. A class of double star sign patterns, denoted by , is introduced. We determine all potentially nilpotent sign patterns in and , and prove that one sign pattern in is potentially stable.
On properties of quadratic matrices.
On rank subtractivity between normal matrices.
On relations between right and left eigenvectors of nonselfadjoint matrix pencils
On separation of eigenvalues by the permutation group
Let A be an invertible 3 × 3 complex matrix. It is shown that there is a 3 × 3 permutation matrix P such that the product PA has at least two distinct eigenvalues. The nilpotent complex n × n matrices A for which the products PA with all symmetric matrices P have a single spectrum are determined. It is shown that for a n × n complex matrix [...] there exists a permutation matrix P such that the product PA has at least two distinct eigenvalues.
On Some new Inclusion Theorems for the Eigenvalues of Partitioned Matrices.
On some spectral characteristics of multiparameter polynomial matrices.
On spaces of matrices with a bounded number of eigenvalues.
On spectra perturbation and elementary divisors of positive matrices.
On symmetric matrices with exactly one positive eigenvalue.
On the 2-norm distance from a normal matrix to the set of matrices with a multiple zero eigenvalue.
On the angles between certain arithmetically defined subspaces of
If and are two families of unitary bases for , and is a fixed number, let and be subspaces of spanned by vectors in and respectively. We study the angle between and as goes to infinity. We show that when and arise in certain arithmetically defined families, the angles between and may either tend to or be bounded away from zero, depending on the behavior of an associated eigenvalue problem.
On the approximation numbers of large Toeplitz matrices.
On the arguments of proper values of normal and unitary transformations
On the asymptotic distributions of certain functional of eigenvalues of correlation matrices
On the automorphisms of the spectral unit ball
Let Ω be the spectral unit ball of Mₙ(ℂ), that is, the set of n × n matrices with spectral radius less than 1. We are interested in classifying the automorphisms of Ω. We know that it is enough to consider the normalized automorphisms of Ω, that is, the automorphisms F satisfying F(0) = 0 and F'(0) = I, where I is the identity map on Mₙ(ℂ). The known normalized automorphisms are conjugations. Is every normalized automorphism a conjugation? We show that locally, in a neighborhood of a matrix with...