Continuity and general perturbation of the Drazin inverse for closed linear operators
N. Castro González, J. J. Koliha, Vladimir Rakočević · Abstract and Applied Analysis · 2002
We study perturbations and continuity of the Drazin inverse of a closed linear operator A and obtain explicit error estimates in terms of the gap between closed operators and the gap between ranges and nullspaces of operators. The results are used to derive a theorem on the continuity of the Drazin inverse for closed operators and to describe the asymptotic behavior of operator semigroups.