Linear fractional transformations and companion matrices
Linear preserver problems and algebraic groups.
Linear preservers of row-dense matrices
Let be the set of all real matrices. A matrix is said to be row-dense if there are no zeros between two nonzero entries for every row of this matrix. We find the structure of linear functions that preserve or strongly preserve row-dense matrices, i.e., is row-dense whenever is row-dense or is row-dense if and only if is row-dense, respectively. Similarly, a matrix is called a column-dense matrix if every column of is a column-dense vector. At the end, the structure of linear...
Linear Transformations Of Tensor Spaces Preserving Decomposable Vectors
Linear transformations of tensor spaces preserving decomposable vectors.
Linearizations of polynomial matrices with symmetries and their applications.
Linearizations of singular matrix polynomials and the recovery of minimal indices.
Matrices and submatrices with constrained invariant factors
Matrices with prescribed characteristic polynomial and submatrices
Matrices with prescribed rows and invariant factors
Matrices with prescribed similarity class and a prescribed nonprincipal submatrix
Multiplicative diagonals of matrix semigroups.
Normal forms of matrices in topoi
Normal matrix polynomials with nonsingular leading coefficients.
Notes on linear combinations of two tripotent, idempotent and involutive matrices that commute.
n-supercyclic and strongly n-supercyclic operators in finite dimensions
We prove that on , there is no n-supercyclic operator with 1 ≤ n < ⌊(N + 1)/2⌋, i.e. if has an n-dimensional subspace whose orbit under is dense in , then n is greater than ⌊(N + 1)/2⌋. Moreover, this value is optimal. We then consider the case of strongly n-supercyclic operators. An operator is strongly n-supercyclic if has an n-dimensional subspace whose orbit under T is dense in , the nth Grassmannian. We prove that strong n-supercyclicity does not occur non-trivially in finite...
Numerical determination of a canonical form of a symplectic matrix.
On a nonnegative irreducible matrix that is similar to a positive matrix
Let A be an n×n irreducible nonnegative (elementwise) matrix. Borobia and Moro raised the following question: Suppose that every diagonal of A contains a positive entry. Is A similar to a positive matrix? We give an affirmative answer in the case n = 4.
On a question of Hills concerning co-transposers
On a theorem by Kronecker. (Short Communication).