5 citations · 13 across the 6 of their papers we have counts for
8 papers
Co-Hopfian virtually free groups and elementary equivalence
Simon André
We prove that two co-Hopfian finitely generated virtually free groups are elementarily equivalent if and only if they are isomorphic. We also prove that co-Hopfian finitely generat…
Simple sharply 2-transitive groups
Simon André, Katrin Tent
We construct simple sharply 2-transitive groups. Our result answers an open question of Peter Neumann. In fact, we prove that every sharply 2-transitive group of characteristic 0 e…
Formal solutions and the first-order theory of acylindrically hyperbolic groups
Simon André, Jonathan Fruchter
We generalise Merzlyakov's theorem about the first-order theory of non-abelian free groups to all acylindrically hyperbolic groups. As a corollary, we deduce that if is an acyl…
Acylindrical hyperbolicity and existential closedness
Simon André
Let be a finitely presented group, and let be a subgroup of . We prove that if is acylindrically hyperbolic and existentially closed in , then is acylindrical…
Elementary subgroups of virtually free groups
Simon André
We give a description of elementary subgroups (in the sense of first-order logic) of finitely generated virtually free groups. In particular, we recover the fact that elementary su…
On Tarski's problem for virtually free groups
Simon André
We give a complete classification of finitely generated virtually free groups up to -elementary equivalence. As a corollary, we give an algorithm that takes as inpu…