Acción dual de las copias, isométricas asintóticamente, de lp (1 ≤ p < ∞) y c0.
We provide new characterizations of acyclic inductive spectra of Fréchet spaces which improve the classical theorem of Palamodov and Retakh. It turns out that acyclicity, sequential retractivity (defined by Floret) and further strong regularity conditions (introduced e.g. by Bierstedt and Meise) are all equivalent. This solves a problem that was folklore since around 1970. For inductive limits of Fréchet-Montel spaces we obtain even stronger results, in particular, Grothendieck's problem whether...
There is a nontrivial gap in the proof of Theorem 5.2 of [2] which is one of the main results of that paper and has been applied three times (cf. [2, Theorem 5.3, (G) in Section 6, Theorem 6.4]). Till now neither the gap has been closed nor a counterexample found. The aim of this paper is to give, by means of some general results, a better understanding of the gap. The proofs that the applications hold will be given elsewhere.
For a given bi-continuous semigroup on a Banach space we define its adjoint on an appropriate closed subspace of the norm dual . Under some abstract conditions this adjoint semigroup is again bi-continuous with respect to the weak topology . We give the following application: For a Polish space we consider operator semigroups on the space of bounded, continuous functions (endowed with the compact-open topology) and on the space of bounded Baire measures (endowed with the weak-topology)....
We construct a metrizable simplex X such that for each n ɛ ℕ there exists a bounded function f on ext X of Baire class n that cannot be extended to a strongly affine function of Baire class n. We show that such an example cannot be constructed via the space of harmonic functions.
Para varios espacios localmente separados, damos aplicaciones lineales no continuas con gráficas cerradas. Uno de los resultados obtenidos contiene el teorema de Mahowald como corolario [7]. Si ε es una clase de espacios localmente convexos separados, estable para límites inductivos y conteniendo los espacios de dimensiones finitas, sea εr la clase de todos los espacios localmente convexos separados tales que si E ∈ ε, F ∈ εr y f es una aplicación lineal de E en F con gráfica cerrada, entonces f...
We introduce new concept of almost demi Dunford–Pettis operators. Let be a Banach lattice. An operator from into is said to be almost demi Dunford–Pettis if, for every sequence in such that in and as , we have as . In addition, we study some properties of this class of operators and its relationships with others known operators.