As we see, the existence of vacuum surfaces and hence the violation of the weak energy condition beyond them is possible if and only if a related spherical solution satisfies the dominant energy condition  ([??] [greater than or equal to] [[??].sub.k] in (20)).
The second type of interiors exists if the related spherical solution satisfies the dominant energy condition. This type of interior is presented by de Sitter vacuum S-surface specified by p = -[rho], which contains de Sitter disk as the bridge.