Weak and strong continuity of representations of topologically pseudocomplete groups in locally convex spaces

A. I. Shtern

Sbornik. Mathematics, Tome 197 (2006) no. 3, pp. 453-473

Résumé

Weak and strong continuity conditions for representations of topological groups in locally convex spaces are considered. In particular, weak continuity conditions of reducible locally equicontinuous representations of a topological group in a locally convex space that define weakly continuous representations in an invariant subspace and in the quotient space by this invariant subspace are investigated. These conditions help one to prove the weak continuity of averages and approximations related to weakly continuous locally equicontinuous quasirepresentations of amenable topological groups. Strong continuity conditions for a representation approximating a quasirepresentation of this kind are related to conditions of automatic strong continuity of weakly continuous representations, and fail to hold for some groups, spaces, and representations. In this connection, strong continuity conditions for weakly continuous representations in quasicomplete barrelled locally convex spaces are indicated for a broad class of topologically pseudocomplete groups (which includes the Čech complete groups and the locally pseudocompact groups). Several examples are discussed, in particular, ones relating to the construction of $\Sigma$-products with distinguished subgroups. Bibliography: 50 titles.

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