Expanders are counterexamples to the ${\ell }^p$ coarse Baum-Connes conjecture

Yeong Chyuan Chung, Piotr W. Nowak

We consider an ${\ell }^p$ coarse Baum-Connes assembly map for $1<p<\infty$, and show that it is not surjective for expanders arising from residually finite hyperbolic groups.