weak*-closed invariant subspaces and ideals of semigroup algebras on foundation semigroups
نویسندگان
چکیده
let s be a locally compact foundation semigroup with identity and be its semigroup algebra. let x be a weak*-closed left translation invariant subspace of in this paper, we prove that x is invariantly complemented in if and only if the left ideal of has a bounded approximate identity. we also prove that a foundation semigroup with identity s is left amenable if and only if every complemented weak*-closed left translation invariant subspace of is invariantly complemented in .
منابع مشابه
Weak*-closed invariant subspaces and ideals of semigroup algebras on foundation semigroups
Let S be a locally compact foundation semigroup with identity and be its semigroup algebra. Let X be a weak*-closed left translation invariant subspace of In this paper, we prove that X is invariantly complemented in if and only if the left ideal of has a bounded approximate identity. We also prove that a foundation semigroup with identity S is left amenab...
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عنوان ژورنال:
journal of sciences, islamic republic of iranناشر: university of tehran
ISSN 1016-1104
دوره 25
شماره 1 2014
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