Bicommutants of Reduced Unbounded Operator Algebras
نویسندگان
چکیده
The unbounded bicommutant (ME′ ) ′′ wc of the reduction of an O*algebra Mvia a given projection E weakly commuting with M is studied, with the aim of finding conditions under which the reduction of a GW*-algebra is a GW*-algebra itself. The obtained results are applied to the problem of the existence of conditional expectations on O*-algebras.
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