Subgroups of the Nottingham group (Q1373204)

The Nottingham group is defined as the subgroup of the automorphism group \(\Aut \mathbb{F}_p((t))\) of the field of formal power series, consisting of automorphisms of the form \(t\to t+\sum_{i=2}^\infty\alpha_it\). This group has received considerable attention from pro-\(p\) group theorists during the last few years, because of certain interesting properties it possesses: it is a finitely generated, just infinite pro-\(p\) group of finite width. Nevertheless, as is shown in the present paper, it is surprisingly large in the sense that every separable pro-\(p\) group can be embedded in it, as a closed subgroup.