%0 Journal Article
%A Cobos Díaz, Fernando
%A Cwikel, M.
%A Matos, P.
%T Best possible Compactness Results of Lions-Peetre Type
%D 2001
%@ 0013-0915
%U https://hdl.handle.net/20.500.14352/57226
%X If T : A0 ! B boundedly and T : A1 ! B compactly, then a result of Lions{Peetre shows that T : A ! B compactly for a certain class of spaces A which are intermediate with respect to A0 and A1. We investigate to what extent such results can hold for arbitrary intermediate spaces A. The `dual' case of an operator S such that S : X ! Y0 boundedly and S : X ! Y1 compactly, is also considered,as well as similar questions for other closed operator ideals.
%~