Mod-$p$ cohomology growth in $p$-adic analytic towers of 3-manifolds

Let M be a compact 3-manifold with infinite fundamental group . Given a homomorphism from to a p-adic analytic group G with dense image, we describe the possible mod-p homology growth of covers Mn of M determined by the congruence subgroups Gn. If d D dim.G/ > 3, this growth is always non-trivial, growing at least as fast as Vol.Mn/ 1/=d . Mathematics Subject Classification (2010). 22E40.