A SURJECTIVITY PROBLEM FOR MATRICES AND NULL CONTROLLABILITY FOR DIFFERENCE AND DIFFERENTIAL MATRIX EQUATIONS
Donal O’Regan, C Buse · DOAJ (DOAJ: Directory of Open Access Journals) · 2020
Let P be a complex polynomial. We prove that the associated polynomial matrix-valued function \tildeP is surjective if for each λ ∈ ℂ the polynomial P-λ has at least a simple zero. The null controllability for difference and differential matrix equations is also presented.