SPHERICALLY SYMMETRICAL NONLINEAR STRUCTURES

We present an analytical method to extract observational predictions a bout the nonlinear evolution of perturbations in a Tolman universe. We assume no a priori profile for them. We solve perturbatively a Hamilt on-Jacobi equation for a timelike geodesic and obtain the null one as a limiting case in two situations: for an observer located in the cent er of symmetry and for a noncentered one. In the first case we find ex pressions to evaluate the density contrast and the number count and lu minosity distance versus redshift relationships up to second order in the perturbations. In the second situation we calculate the CMBR aniso tropies at large angular scales produced by the density contrast and b y the asymmetry of the observer's location, up to first order in the p erturbations. We develop our argument in such a way that the formulas are valid for any shape of the primordial spectrum.