Completeness in the Mackey topology
Funkcionalʹnyj analiz i ego priloženiâ, Tome 49 (2015) no. 2, pp. 21-33.

Voir la notice de l'article provenant de la source Math-Net.Ru

Bonet and Cascales [Non-complete Mackey topologies on Banach spaces, Bulletin of the Australian Mathematical Society, 81, 3 (2010), 409–413], answering a question of M. Kunze and W. Arendt, gave an example of a norming norm-closed subspace $N$ of the dual of a Banach space $X$ such that $\mu(X,N)$ is not complete, where $\mu(X,N)$ denotes the Mackey topology associated with the dual pair $\langle X,N\rangle$. We prove in this note that we can decide on the completeness or incompleteness of topologies of this form in a quite general context, thus providing large classes of counterexamples to the aforesaid question. Moreover, our examples use subspaces $N$ of $X^*$ that contain a predual $P$ of $X$ (if exists), showing that the phenomenon of noncompleteness that Kunze and Arendt were looking for is not only relatively common but illustrated by “well-located” subspaces of the dual. We discuss also the situation for a typical Banach space without a predual—the space $c_0$—and for the James space $J$.
Keywords: Mackey-star topology, completeness, local completeness, Banach space.
@article{FAA_2015_49_2_a2,
     author = {A. J. Guirao and V. Montesinos},
     title = {Completeness in the {Mackey} topology},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {21--33},
     publisher = {mathdoc},
     volume = {49},
     number = {2},
     year = {2015},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_2015_49_2_a2/}
}
TY  - JOUR
AU  - A. J. Guirao
AU  - V. Montesinos
TI  - Completeness in the Mackey topology
JO  - Funkcionalʹnyj analiz i ego priloženiâ
PY  - 2015
SP  - 21
EP  - 33
VL  - 49
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/FAA_2015_49_2_a2/
LA  - ru
ID  - FAA_2015_49_2_a2
ER  - 
%0 Journal Article
%A A. J. Guirao
%A V. Montesinos
%T Completeness in the Mackey topology
%J Funkcionalʹnyj analiz i ego priloženiâ
%D 2015
%P 21-33
%V 49
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/FAA_2015_49_2_a2/
%G ru
%F FAA_2015_49_2_a2
A. J. Guirao; V. Montesinos. Completeness in the Mackey topology. Funkcionalʹnyj analiz i ego priloženiâ, Tome 49 (2015) no. 2, pp. 21-33. http://geodesic.mathdoc.fr/item/FAA_2015_49_2_a2/

[1] J. Bonet, B. Cascales, “Non-complete Mackey topologies on Banach spaces”, Bull. Aust. Math. Soc., 81:3 (2010), 409–413 | DOI | MR | Zbl

[2] M. Fabian, P. Habala, P. Hájek, V. Montesinos, V. Zizler, Banach Space Theory. The Basis for Linear and Nonlinear Analysis, CMS Books in Math., Springer-Verlag, New York, 2011 | DOI | MR | Zbl

[3] P. Pérez-Carreras, J. Bonet, Barreled Locally Convex Spaces, North-Holland Mathematical Studies, 131, North-Holland, Amsterdam, 1987 | MR

[4] P. Civin, B. Yood, “Quasi-reflexive spaces”, Proc. Amer. Math. Soc., 8:5 (1957), 906–911 | DOI | MR | Zbl

[5] J. Diestel, Sequences and Series in Banach Spaces, Graduate Texts in Math., 92, Springer-Verlag, New York, 1984 | DOI | MR

[6] K. Floret, Weakly Compact Sets, Lecture Notes in Math., 801, Springer-Verlag, Berlin, 1980 | DOI | MR | Zbl

[7] G. Godefroy, “Boundaries of a convex set and interpolation sets”, Math. Ann., 277:2 (1987), 173–184 | DOI | MR | Zbl

[8] R. C. James, “A nonreflexive Banach space isometric with its second conjugate”, Proc. Nat. Acad. Sci. USA, 37 (1951), 174–177 | DOI | MR | Zbl

[9] G. Köthe, Topological Vector Spaces I, Springer-Verlag, New York, 1969 | MR | Zbl