Cosmological bounces and Lorentzian wormholes in Galileon theories with
  an extra scalar field
  We study whether it is possible to design a "classical" spatially flat
bouncing cosmology or a static, spherically symmetric asymptotically flat
Lorentzian wormhole in cubic Galileon theories interacting with an extra scalar
field. We show that bouncing models are always plagued with gradient
instabilities, while there are always ghosts in wormhole backgrounds.
