Cosmological black holes from self-gravitating fields

摘要: Both cosmological expansion and black holes are ubiquitous features of our observable Universe, yet exact solutions connecting the two have remained elusive. To this end, we study self-gravitating classical fields within dynamical spherically symmetric that can describe in an expanding universe. After attempting a perturbative approach known black-hole solution with scalar hair, show by methods unique field action first-order derivatives source shear-free around hole requires noncanonical kinetic terms. The resulting is incompressible limit k-essence, otherwise as cuscuton theory, spacetime it describes McVittie metric. We further to vacuum Ho\v{r}ava-Lifshitz gravity anisotropic Weyl symmetry.