Abstract
An operatorT on\(\mathcal{H}\) is called strongly irreducible ifT does not commute with any nontrivial idempotent operator. In this paper, we first show that each nest algebra τ(\(\mathcal{N}\)) has strongly irreducible operators. Secondly, we obtain a characterization of operators which can be uniquely written as a direct sum of finitely many strongly irreducible operators. Finally, we characterize the strongly irreducibility of operators in a nest algebra τ(\(\mathcal{N}\)).
Similar content being viewed by others
References
[Bar-Dav] J. Barria and K.R. Davidson, Unicellar operators, Trans. Amer. Math. Soc., (284) 1984, 229–246.
[Dav] K.R. Davidson, Nest algebra, Pitman Res., Notes Math. 191, Longman Harlow, Essex, 1988.
[Dix] J. Dixmier, Les operateurs permutables a loperateur integral, Fas. 2, Portugal Math. (8) 1949, 73–84.
[Don] W.F. Donoghue, The lattice of invariant subspaces of a completly continuous quasinilpotent transformation, Pacific J. Math., 1957, 1031–1035.
[Fia] L.A. Fialkow, A note on the range of the operatorX → AX-XB, Illinois J. Math., (25), 1981, 112–124.
[Fon-Jia] C.K. Fong and Jiang, C.L., Approximation by Jordan type operators, Houston J. Math., (19) 1993, 51–62.
[Gil] F. Gilfeather, Strong reducibility of operators, Ind. Univ. Math. J., (22), 1972, 393–397.
[Har-Lon] K.J. Harrison and W.E. Longstaff, An invariant subspace lattice of order typew+w+1, Proc. Amer. Math., (79), 1980, 45–49.
[Her] D.A. Herrero, Approximation of Hilbert space operators, Pitman Res., Notes Math., 224, Longman Harlow, Essex, 1990.
[Her-Jia] D.A. Herrero and C.L. Jiang, Limits of strongly irreducible operators and the Riesz decomposition theorem, Mich. Math. J., (37), 1990, 283–291.
[Ji-Jia-Wan] Y.Q. Ji, C.L. Jiang, Z.Y. Wang, Essentially normal+small compact=strongly irreducible, Chinese Journal of Comtemporary Mathematics (to appear).
[Jia] Z.J. Jiang, Topics in operator theory, Seminar Reports in Functional analysis, Jilin University, Changchung (in chinese), 1979.
[Jia] C.L. Jiang, Similarity Reducibility and Approximation of the Cowen-Douglas operators, J. Operator Theory 32, 1994, 77–89.
[Jia-Wan] C.L. Jiang and Z.Y. Wang, A class of strongly irreducible operators with nice properties, J. Operator Theory (to appear).
[Nik] N.K. Nikolskii, Selected problems of weighted approximation and spectral analysis, Proc. Steklov. Inst. Math., (120), 1974, Amer. Math. Soc., Providence, 1976.
[Yak] B.V. Yakubovic, Invariant subspaces of weighted shift operators, Zapiski Nauk. Sem. Lomi., (141) 1985, 100–143.
Author information
Authors and Affiliations
Additional information
This project was partially supported by National Natural Science Foundation of China.
Rights and permissions
About this article
Cite this article
Ji, Y.Q., Jiang, C.L. & Wang, Z.Y. The strongly irreducible operators in nest algebras. Integr equ oper theory 28, 28–44 (1997). https://doi.org/10.1007/BF01198794
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF01198794