Cosmological stealths with nonconformal couplings
  In this paper we reconsider the existence of stealth fields during the
evolution of our Universe by admitting more realistic nonminimal couplings to
gravity than the conformal one. In the framework of the FRW cosmology we found
that inhomogeneous stealths, as those enabled in the conformal case, are only
allowed in de Sitter backgrounds. In particular, it is shown that the
homogeneous stealths resulting from nonconformal couplings can coexist with
each kind of matter dominant in the several phases characterizing the evolution
of our Universe according to the $\Lambda$CDM model.
