subjected to the conditions 1 + f > 0 and F > 0 , where f ( R ) and F ( R ) are arbitrary functions, ρ ρ is the matter density and finally primes denote differentiation with respect to R . We can also assume F ′ > 0 and r ′ > 0 that excludes cases resulting in crossing of material particles during its motion. To each particle there corresponds a value of R , the function r ( τ τ , R ) and its time derivative respectively provides its law of motion and radial velocity. An interesting property of the solution described above is that when f ( R ) and F ( R ) are plotted as functions of R , the form of these functions plotted for the range R ∈ ∈ [ 0 , R 0 ] is independent of how these functions will be plotted for R > R 0 . This prediction is evidently similar to the Newtonian theory. The total mass within the sphere R = R 0 is given by