| Abstract: | In this paper we study holomorphic families of subspaces of a Banach space, which are parametrized by some analytic space. We consider the question of the existence of a holomorphic complement for a given family. It turns out that such a complement does always exist if the basic space is a Stein space, provided for each fixed value of the parameter the subspaces of the family are complemented. From this follows, in particular, the existence of a holomorphic left inverse of a holomorphic operator function, provided such a left inverse exists for each fixed value of the parameter. The latter result gives a positive answer to a question formulated by I.C. Gohberg in a personal conversation with the author.Note of the Editor: This paper was originally published in "Mat. Issled. (Kishinev) 5, vyp 4 (18) (1970), 153–165 . The editor is grateful to K. Clancey, W. Kaballo and G. Ph. A. Thijsse for preparing the translation from Russian.Note of the Editor: After the appearance of the original version of the above paper the author informed the editor of Mat. Issled (see Mat. Issled. (Kishinev) 6, vyp (19) (1971), 180) that Corollaries 2 and 3 of Theorem 2 are contained in the papers of G.R. Allan, J. London Math. Soc. 42 (1967), 463–470 and 509–513. |
