Virtual particles versus superconductive vacuum polarizations in interacting systems

The structure of the reference vacuum state plays a very important role in a theoretical dynamic description of interacting particles. This structure is generated by the residual interaction acting between the valence particles and, in systems under extreme high temperature and consequently high pressure, cannot be treated in the framework of the perturbation theory. In this paper we elaborate a nonperturbative approximation to include the vacuum-polarization effects of superconductive type in the calculation of the many-body dynamics. In this proposed model, the wave functions of the system are characterized by the strong coupling of the valence particles with the intrinsic vacuum states. These are associated with (a) superconductive vacuum polarizations, and (b) superconductive virtual particles formed coupling the vacuum excitations to the non-normal parity states of the system. The coupling of the valence particles with the vacuum excitations (a) and (b), in this paper, is generated within the equations of motion methods which, in the limit of factorization methods defined to compute the matrix elements of the nuclear Hamiltonian in the resulting complex states, and with the use of energy-dependent linearization approximations, introduced to generate the superconductive collective modes, are of easy application in the low-energy domain of the interacting systems. The energy-dependent linearization approximations define collective modes which are loose and freely moving in this low-energy domain, while strongly interacting with increasing energy