Search
Now showing items 1-2 of 2
Distinguishing geometries using finite quotients
(Mathematical Sciences PublishersGeometry and Topology, 2017-02-10)
We prove that the profinite completion of the fundamental group of a compact 3-manifold M satisfies a Tits alternative: if a closed subgroup H does not contain a free pro-p subgroup for any p, then H is virtually soluble, ...
Undecidability and the developability of permutoids and rigid pseudogroups
(Cambridge University PressForum of Mathematics, Sigma, 2017-03-20)
A $\textit{permutoid}$ is a set of partial permutations that contains the identity and is such that partial compositions, when defined, have at most one extension in the set. In 2004 Peter Cameron conjectured that there ...