Existence of black holes in Friedmann-Robertson-Walker universe   dominated by dark energy
  We study the existence of black holes in a homogeneous and isotropic expanding Friedmann-Robertson-Walker (FRW) universe dominated by dark energy. We show that black holes can exist in such a universe by considering some specific McVittie solutions. Although these solutions violate all three energy conditions, the FRW background does satisfy the weak energy condition. 
Zhong-Heng Li and Anzhong Wang