We prove a subgaussian extension of a Gaussian result on embedding subsets of a Euclidean space into normed spaces. Using the concentration of a random subgaussian vector around its mean we obtain an isomorphic (rather than almost isometric) result, under an additional cotype assumption on the normed space considered.

We show that if G is a non-elementary torsion-free word hyperbolic group then there exists another word hyperbolic group G, such that G is a subgroup of G but G is not quasiconvex in G.

In 1962–63, M. Nagata showed that an abstract variety could be embedded into a complete variety. Later, P. Deligne translated Nagata’s proof into the language of schemes, but did not publish his notes. This paper, which is to appear as an appendix in a forthcoming book, gives an elaboration of Deligne’s notes. It also contains some complementary results on extending divisors and vector sheaves ...

In this paper, we will present an explicit construction of Harvey Friedman which to every finitely generated group G associates a 2-generator subgroup KG 6 Sym(N) such that G embeds into KG and such that if G ∼= H, then KG = KH .