Full paper in PDF:
$% K. D. Bierstedt and J. Bonet, Density conditions in Fréchet and (DF)-spaces, Rev. Mat. Univ. Complut. Madrid 2 (1989), supplementary, 59–75.%$

Density Conditions in Fréchet and (DF)-Spaces

Klaus D. BIERSTEDT and José BONET
FB 17, Mathemathik
Universität-GH-Paderborn
Postfach 16 21 D-4790 Paderborn
Federal Republic of Germany
Departamento de Matemáticas
E.T.S. Arquitectura
Universidad Politécnica de Valencia
Camino de Vera
E-46071 Valencia Spain

ABSTRACT

We survey our main results on the density condition for Fréchet spaces and on the dual density condition for (DF)-spaces (cf. Bierstedt and Bonet (1988)) as well as some recent developments.

At the end of section 1, we include a new result on the projective tensor product of two Fréchet spaces. Taskinen’s construction of counterexamples to Grothendieck’s “problème des topologies” yields Fréchet spaces E  , F  with the density condition such that   ^
E ox pF  is not (even) distinguished (see Taskinen (to appear)). We prove now that the negative solution of the “problème des topologies” is, in fact, the only obstruction: For two Fréchet spaces E  and F  with the density condition, E ox ^pF  has the density condition as well (and hence is distinguished) whenever the “problème des topologies” has a positive solution for the pair (E,F )  .

1980 Mathematics Subject Classification (1985 revision): 46A06, 46A07, 46A09, 46A020, 46A32, 46A45, 46M05, 46M40.