Quantum effects in Friedmann space and creation of macroscopic mass (Q916122)

The author investigates the particle creation out of the vacuum within an expanding Friedmann-Universe. The backreaction of the created particles is taken into account assuming that the classical gravitational field plays two roles, that of an observer and that of the energetic reservoir. So the created particles are obtained as real (and not as virtual) ones by the method of diagonalization of the instantaneous Hamiltonian. The vacuum polarization terms are interpreted by an effective alteration of the gravitational constant in such a way that it is much smaller before particle creation. The consequences of this change of the gravitational constant is discussed summarily. Finally the influence of self- interaction terms within the scalar particle-field equation is investigated in connection with gauge symmetry breaking.