arXiv subjects

Menny Aka

Publications and source records attributed to Menny Aka.

20 records · Page 2Linked to original sources

arXiv2011

Arithmetic groups with isomorphic finite quotients

Two finitely generated groups have the same set of finite quotients if and only if their profinite completions are isomorphic. Consider the map which sends (the isomorphism class of) an S-arithmetic group to (the isomorphism class of) its profinite completion. We show that for a wide class of S-arithmetic groups, this map is finite to one, while the the fibers are of unbounded size.

math.GR↗

arXiv2011

Profinite completions and Kazhdan's property (T)

We show that property (T) is not profinite, that is, we construct two finitely generated residually finite groups which have isomorphic profinite completions while one admits property (T) and the other does not. This settles a question raised by M. Kassabov.

math.GR↗