On the Coupling Between Gravity and Electromagnetism Through Quantum Vacuum

The possible unification between electromagnetism and gravity is one of greatest challenges in Physics. According to the so-called "Zero-Point Field Inertia Hypothesis"inertia and gravity could be interpreted, through a semi-classical approach, as the electromagnetic reaction force to the interaction between charged elementary particles contained in a body and quantum vacuum fluctuating electromagnetic modes interacting with them. In a late paper this author, sharing this idea as a starting point but moving within the framework of QFT, proposed a novel model in which inertia emerges from a superradiant phase transition of quantum vacuum due to the coherent interaction between matter-wave and em fields quanta. In both the approaches a resonant-type mechanism is involved in describing the dynamic interaction between a body and ZPF in which it is "immersed". So it is expected that if a change in the related resonance frequency is induced by modifying the boundary conditions as, for example, through the introduction of a strong electromagnetic field of suitable frequency, the inertial and gravitational mass associated to that body will also be modified. In this paper we have shown, also basing on previous results and starting from the assumption that not only inertia but also gravitational constant G could be truly a function of quantum vacuum energy density, that the application of an electromagnetic field is able to modify the ZPF energy density and, consequently, the value of G in the region of space containing a particle or body. This result particularly suggests a novel interpretation of the coupling between electromagnetic and gravitational interaction ruled by the dynamical features of ZPF energy. Apart from its theoretical consequences, this model could also proposes new paths towards the so-called ZPF-induced gravitation with very interesting applications to advanced technology.