Saturating constructions for normed spaces

Abstract.

We prove several results of the following type: given finite dimensional normed space V there exists another space X with log dim X = O(log dim V) and such that every subspace (or quotient) of X, whose dimension is not “too small,” contains a further subspace isometric to V. This sheds new light on the structure of such large subspaces or quotients (resp. large sections or projections of convex bodies) and allows us to solve several problems stated in the 1980s by V. Milman.