Asymptotic cones of finitely presented groups

Let G be a connected semisimple Lie group with at least one absolutely simple factor S such that R-rank(S) is at least 2, and let $\mathrm{\Gamma }$ be a uniform lattice in G. (a) If $CH$ holds, then $\mathrm{\Gamma }$ has a unique asymptotic cone up to homeomorphism. (b) If $CH$ fails, then $\mathrm{\Gamma }$ has $2^{2^{\omega }}$ asymptotic cones up to homeomorphism.