Abstract
In 1978 E. Albrecht constructed a Banach space operator which is decomposable in the sense of C. Foias, but not strongly decomposable. In the present note we describe a method which allows to construct examples of this kind in a systematic and much simpler way. In particular, we exhibit a decomposable, but not strongly decomposable operator on a Hilbert space and thus answer a corresponding question of M.Radjabalipour.
Similar content being viewed by others
References
Albrecht,E.: On two questions of I. Colojoarã and C. Foias, Manuscripta Math. 25(1978), 1–15.
Albrecht,E.: On decomposable operators, Integral Equations and Operator Theory 2(1979), 1–10.
Albrecht,E. and Eschmeier, J.: Functional models and local spectral theory, Preprint.
Apostol,C.: Restrictions and quotients of decomposable operators in a Banach space, Rev. Roum. Pures Appl. 13(1968), 147–150.
Bishop,E.: A duality theorem for an arbitrary operator, Pacific J. Math. 9 (1959), 379–394.
Colojoară,I. and Foias, C.: Theory of generalized spectral operators, New York: Gordon and Breach 1968.
Foias,C.: Spectral maximal spaces and decomposable operators in Banach spaces, Arch. Math. 14(1963), 341–349.
Halmos,P.R.: A Hilbert space problem book, Princeton: Van Nostrand 1967.
Köthe,G.: Topologische lineare Räume I, 2. Aufl. Berlin-Heidelberg-New York: Springer-Verlag 1966.
Lang,S.: Real analysis, Reading Massachusetts: Addison-Wesley 1969.
Putinar,M.: Spectral theory and sheaf theory I, Operator Theory: Advances and Applications Vol. 11 (Timisoara and Herculane), 283–297. Basel-Boston-Stuttgart: Birkhäuser Verlag 1983.
Radjabalipour,M.: Decomposable operators, Bull. Iran. Math. Soc. 9(1978), 1–49.
Vasilescu,F.-H.: Analytic functional calculus and spectral decompositions, Bucharest and Dordrecht: Ed. Academiei and D.Reidel Co. 1982.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Eschmeier, J. A decomposable Hilbert space operator which is not strongly decomposable. Integr equ oper theory 11, 161–172 (1988). https://doi.org/10.1007/BF01272116
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01272116