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Classes of operators on vector valued integration spaces

Published online by Cambridge University Press:  09 April 2009

J. E. Jamison
Affiliation:
Department of Mathematics, Memphis State University Memphis Tennessee 38152 USA
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Abstract

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Let Lp(Ω, K) denote the Banach space of weakly measurable functions F defined on a finite measure space and taking values in a separable Hilbert space K for which ∥ Fp = ( ∫ | F(ω) |p)1/p < + ∞. The bounded Hermitian operators on Lp(Ω, K) (in the sense of Lumer) are shown to be of the form , where B(ω) is a uniformly bounded Hermitian operator valued function on K. This extends the result known for classical Lp spaces. Further, this characterization is utilized to obtain a new proof of Cambern's theorem describing the surjective isometries of Lp(Ω, K). In addition, it is shown that every adjoint abelian operator on Lp(Ω, K) is scalar.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1977

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