Sequential convergence in topological vector spaces.
In the present paper we deal with sequential convergences on a vector lattice which are compatible with the structure of .
In this paper we prove the following result: an inductive limit is regular if and only if for each Mackey null sequence in there exists such that is contained and bounded in . From this we obtain a number of equivalent descriptions of regularity.
A notion of an almost regular inductive limits is introduced. Every sequentially complete inductive limit of arbitrary locally convex spaces is almost regular.
The Hahn–Banach theorem implies that if is a one dimensional subspace of a t.v.s. , and is a circled convex body in , there is a continuous linear projection onto with . We determine the sets which have the property of being invariant under projections onto lines through subject to a weak boundedness type requirement.
The Blaschke–Kakutani result characterizes inner product spaces , among normed spaces of dimension at least 3, by the property that for every 2 dimensional subspace there is a norm 1 linear projection onto . In this paper, we determine which closed neighborhoods of zero in a real locally convex space of dimension at least 3 have the property that for every 2 dimensional subspace there is a continuous linear projection onto with .
An elementary construction for an abundance of vector topologies on a fixed infinite dimensional vector space such that has not the Hahn-Banach extension property but the topological dual separates points of from zero is given.
We give characterizations of certain properties of continuous linear maps between Fréchet spaces, as well as topological properties on Fréchet spaces, in terms of generalizations of Behrends and Kadets small ball property.
We investigate stability of various classes of topological algebras and individual algebras under small deformations of multiplication.