Weighted (LF)-spaces of Continuous Functions

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（LF）-空间的完备性

设（E，ξ）=indlim（E．，ξn）为Frechel空间序列的诱导权限，我们证明了：若每个（Enξ|En）正速完备，则（E，ξ）=indlim（En，ξn）为完备，进而证明了；若对于每个自然数n，存在自然数m（n）使对于任意p≥m（n）有En；则（E，ξ）为完备．     

Remarks on regular (LF)-spaces

Developing ideas found in a recent paper of Gilsdorf to arbitrary topological vector spaces (tvs) one shows that a Hausdorff (LB) _tv -spaceE is regular provided every null-sequence inE has a series convergent subsequence inE. Received by the editors 1980Mathematics Subject Classification (1985 Revision) 46A12.     

On the completion of (LF)-spaces

Once the existence of metrizable (LF)-spaces was discovered, the problem whether the completion of an (LF)-space is or is not an (LF)-space was answered in the negative, because no (LF)-space can be a Fréchet space. However, some (non-metrizable) (LF)-spaces are complete, e.g. the classical Köthe's strict (LF)-spaces. In this paper we will carry out a thorough study of the completeness of (LF)-spaces stressing upon the stable completion properties of (LB)-spaces. A basic tool for handling this problem is an Open Mapping Theorem for completions of (LF)-spaces, which is also proved in the present paper.This research, supported by a Fulbright-MEC fellowship, was carried out during the author's visit at the University of Maryland while on leave from the University of Extremadura. The author is grateful to Professor S. A. Saxon for very helpful conversation and, especially, for calling his attention to the problem of completions of (LF)-spaces.     

A note on biduals of strict (LF)-spaces

Grothendieck asked in 1954 in [1] the following questions. (1) Is the bidual of a strict inductive limit of a sequence of locally convex spaces the inductive limit of the biduals? (2) Is the bidual of a strict (LF)-space again an (LF)-space? (3) Is the bidual of a strict (LF)-space complete? M. Valdivia gave a (negative) answer to the first question in 1979 in [5]. Since his counterexample is not an (LF)-space, problem (2) remained open. The aim of this note is to present a negative solution to questions (2) and (3). The answer to question (2) is negative even if every step of the (LF)-space is distinguished, in which case the strong bidual is complete by a result of Grothendieck. Moreover, we show that the strong dual of a strict (LF)-space need not be countably barrelled.     

(DFS)-spaces of holomorphic functions invariant under differentiation

Let be a bounded convex domain, A^−∞(G) be the (DFS)-space of all holomorphic functions of polynomial growth on G and A^∞(G) be the Fréchet space of C^∞-functions on closure of G which are holomorphic on G. With the help of the Laplace transform we describe the strong dual of A^−∞(G) and prove that A^−∞(G) is the unique (DFS)-space H such that the space A^∞(G) is contained in H, H is embedded continuously in A^−∞(G) and H is invariant under differentiation.     

Affine functions on CAT (κ)-spaces

We describe affine functions on spaces with an upper curvature bound.     

Projective limits of weighted (LB)-spaces of continuous functions

Countable projective spectra of countable inductive limits, called (PLB)-spaces, of weighted Banach spaces of continuous functions are investigated. It is characterized when the derived projective limit functor vanishes in terms of the sequences of the weights defining the spaces. The locally convex properties of the corresponding projective limits are analyzed, too. Received: 30 January 2009     

Spaces of measurable functions

For a metrizable space X and a finite measure space (Ω, $\mathfrak{M}$ , µ), the space M _µ(X) of all equivalence classes (under the relation of equality almost everywhere mod µ) of $\mathfrak{M}$ -measurable functions from Ω to X, whose images are separable, equipped with the topology of convergence in measure, and some of its subspaces are studied. In particular, it is shown that M _µ(X) is homeomorphic to a Hilbert space provided µ is (nonzero) nonatomic and X is completely metrizable and has more than one point.     

Fréchet-valued holomorphic functions on compact sets in (DFN)-spaces

We establish the equivalence between the weak holomorphicity and holomorphicity of Fréchet-valued functions on compact polydisks in (DFN)-spaces. Moreover, the relations between separately holomorphic functions and holomorphic functions on compact polydisks in (DFN)-spaces are also given. Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 60, No. 11, pp. 1578–1584, November, 2008.     

(a)-spaces and selectively (a)-spaces from almost disjoint families

We investigate a selective version of property (a) and prove a number of results showing that, under certain set theoretical conditions, (a) spaces and selectively (a) spaces behave in a very similar way, at least for separable spaces. Several results regarding the presence of the referred selective version in spaces from almost disjoint families are established; in particular, we give a combinatorial characterization of such presence. Consistent set theoretical hypotheses implying equivalence between being (a) and being selectively (a) within the referred class are presented, as well as hypotheses implying non-equivalence. We also show that the Continuum Hypothesis is independent of the statement asserting the above mentioned equivalence. The paper finishes by presenting some notes and questions on the role of set theoretical assumptions in the subject.