Pseudo-completeness in linear metrizable spaces
It is proved that every real metrizable locally convex space which is not nuclear contains a closed additive subgroup K such that the quotient group G = (span K)/K admits a non-trivial continuous positive definite function, but no non-trivial continuous character. Consequently, G cannot satisfy any form of the Bochner theorem.
It is proved that if a metrizable locally convex space is not nuclear, then it does not satisfy the Lévy-Steinitz theorem on rearrangement of series.
Suppose that is a Fréchet space, is a regular method of summability and is a bounded sequence in . We prove that there exists a subsequence of such that: either (a) all the subsequences of are summable to a common limit with respect to ; or (b) no subsequence of is summable with respect to . This result generalizes the Erdös-Magidor theorem which refers to summability of bounded sequences in Banach spaces. We also show that two analogous results for some -locally convex spaces...
We give a representation of the spaces as spaces of vector-valued sequences and use it to investigate their topological properties and isomorphic classification. In particular, it is proved that is isomorphic to the sequence space , thereby showing that the isomorphy class does not depend on the dimension N if p=2.