Cosmological domain walls coupled to gravity

We study properties of cosmological domain walls coupled to gravity, where the domain walls are described by nonminimal ${\phi }^4$ models with broken symmetry. The static and planar-symmetric configurations of the domain wall are assumed. We obtain some typical solutions numerically. The oscillating tails of the domain wall are found in some region of a parameter space. The cosmological implication of the domain-wall formation is also discussed.