Magnetic black universes and wormholes with a phantom scalar
  We construct explicit examples of globally regular static, spherically
symmetric solutions in general relativity with scalar and electromagnetic
fields which describe traversable wormholes (with flat and AdS asymptotics) and
regular black holes, in particular, black universes. A black universe is a
nonsingular black hole where, beyond the horizon, instead of a singularity,
there is an expanding, asymptotically isotropic universe. The scalar field in
these solutions is phantom (i.e., its kinetic energy is negative), minimally
coupled to gravity and has a nonzero self-interaction potential. The
configurations obtained are quite diverse and contain different numbers of
Killing horizons, from zero to four. This substantially widens the list of
known structures of regular black hole configurations. Such models can be of
interest both as descriptions of local objects (black holes and wormholes) and
as a basis for building nonsingular cosmological scenarios.
