Spherically symmetrical singular hypersurfaces in conformal gravity

The surface energy-momentum tensor was obtained for the action of an ideal fluid with a variable number of particles in Euler variables. It is shown that in the absence of external fields, “external pressure” and “external flow” are associated with the production of particles in a double layer. The equations of motion along with the Lichnerowicz conditions are expressed using invariants of spherical geometry for timelike and spacelike spherically symmetric singular hypersurfaces. It is shown that for spherically symmetric thin shells the two-dimensional scalar curvature and the two-dimensional Laplacian of the radius are continuous. Spherically symmetric timelike and spacelike singular hypersurfaces separating two solutions of spherically symmetric conformal gravity are investigated as applications, in particular, various vacua and Vaidya-type solutions are used.