Drazin Inverses of Operators with Rational Resolvent
نویسندگان
چکیده
Let A be a bounded linear operator on a Banach space such that the resolvent of A is rational. If 0 is in the spectrum of A, then it is well known that A is Drazin invertible. We investigate spectral properties of the Drazin inverse of A. For example we show that the Drazin inverse of A is a polynomial in A.
منابع مشابه
Analytic Perturbation of Generalized Inverses
We investigate the analytic perturbation of generalized inverses. Firstly we analyze the analytic perturbation of the Drazin generalized inverse (also known as reduced resolvent in operator theory). Our approach is based on spectral theory of linear operators as well as on a new notion of group reduced resolvent. It allows us to treat regular and singular perturbations in a unified framework. W...
متن کاملPerturbation Analysis of Reduced Resolvents and Generalized Inverses
We investigate analytic perturbations of the reduced resolvent of a nite-dimensional linear operator (also known as Drazin inverse in the linear algebra literature). Our approach is based on spectral theory of linear operators as well as on a new notion of group reduced resolvent. It allows to treat regular and singular perturbations in a uniied framework. We provide an algorithm for computing ...
متن کاملThe representation of the Drazin inverse of anti-triangular operator matrices based on resolvent expansions
Keywords: Drazin inverse Anti-triangular operator matrix Resolvent expansion a b s t r a c t This paper deals with the anti-triangular operator matrix M ¼ A B C 0 with A 2 ¼ A and CA p B ¼ 0. Using the resolvent expansion technique, we obtain the explicit representation of the Drazin inverse of M, in terms of its entries and the Drazin inverses of the entries and their compositions. The result ...
متن کاملGröbner basis computation of Drazin inverses with multivariate rational function entries
In this paper we show how to apply Gröbner bases to compute the Drazin inverse of a matrix with multivariate rational functions as entries. When the coefficients of the rational functions depend on parameters, we give sufficient conditions for the Drazin inverse to specialize properly. In addition, we extend the method to weighted Drazin inverses. We present an empirical analysis that shows a g...
متن کاملContinuity and General Perturbation of the Drazin Inverse for Closed Linear Operators
In this paper, we investigate a perturbation of the Drazin inverse AD of a closed linear operator A; the main tool for obtaining the estimates is the gap between subspaces and operators. By (X) we denote the set of all closed linear operators acting on a linear subspace of X to X , where X is a complex Banach space. We write (A), (A), (A), ρ(A), σ(A), and R(λ,A) for the domain, nullspace, range...
متن کامل