Polynomial Matrices with Hermitian Coefficients and a Generalization of the Eneström–kakeya Theorem
نویسنده
چکیده
Polynomial matrices G(z) = Izm−Cizi with hermitian coefficients Ci are studied. The assumption ∑ |Ci| I implies that the characteristic values of G(z) lie in the closed unit disc. The characteristic values of modulus one are roots of unity. An extension of the Eneström– Kakeya theorem is proved and a stability criterion for a system of difference equations is given. Mathematics subject classification (2000): 15A33, 15A24, 15A57, 26C10, 30C15, 39A11.
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تاریخ انتشار 2008