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Closed linear operators with domain containing their range

Published online by Cambridge University Press:  20 January 2009

Schôichi Ôta
Affiliation:
Department of Mathematics, Kyushu University 33, Fukuoka 812, Japan
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In connection with algebras of unbounded operators, Lassner showed in [4] that, if T is a densely defined, closed linear operator in a Hilbert space such that its domain is contained in the domain of its adjoint T* and is globally invariant under T and T*,then T is bounded. In the case of a Banach space (in particular, a C*-algebra) weshowed in [6] that a densely defined closed derivation in a C*-algebra with domaincontaining its range is automatically bounded (see the references in [6] and [7] for thetheory of derivations in C*-algebras).

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1984

References

1.Batty, C. J. K., Dissipative mappings and well-behaved derivations, J. London Math. Soc (2), 18 (1978), 527533.CrossRefGoogle Scholar
2.Davies, E. B., One-parameter semi-groups (New York-San Francisco-London, Academic Press, 1980).Google Scholar
3.Kato, T., Perturbation theory for linear operators (Berlin-Heidelberg-New York, Springer, 1966).Google Scholar
4.Lassner, G., Topological algebras of operators, Rep. Math. Phys. 3 (1972), 279293.CrossRefGoogle Scholar
5.Lummer, G. and Phillips, R. S., Dissipative operators in a Banach space, Pacific J. Math. 11 (1961), 679689.CrossRefGoogle Scholar
6.Ota, S., Closed derivations in C*-algebras, Math. Ann. 257 (1981), 239250.Google Scholar
7.Ota, S., Commutants of unbounded derivations in C*-algebras, J. Reine Angew. Math. 347 (1984), 2132.Google Scholar
8.Stone, M. H., Linear transformations in Hilbert space and their applications to analysis (Amer. Math. Soc. Colloq. Publ. 15, Providence, R.I., 1932).Google Scholar