It was demonstrated (gr-qc/9910036) that the gravitational and inertial masses are correlated by an a dimensional factor, which depends on the incident ( or emitted) radiation upon the particle. There is a direct correlation between the radiation absorbed( or radiated) by the particle and its gravitational mass, independently of the inertial mass. Only in the absence of electromagnetic radiation the mentioned factor becomes equal to one. On the other hand, in specific electromagnetic conditions, it can be reduced, nullified or made negative. This means that there is, the possibility of the gravitational masses can be reduced, nullified or made negative by means of electromagnetic radiation. This unexpected theoretical result was confirmed by an' experiment using Extra-Low Frequency(ELF) radiation on ferromagnetic material (gr-qc/0005107). Recently another experiment using UV light on phosphorescent plastic have confirmed the phenomenon. We present a complete explanation for the alterations of the gravitational field in luminescent materials. This work indicates that the alterations of the gravitational field can be sufficiently strong to invert the gravity on luminescent materials.
There is an electromagnetic factor of correlation between gravitational mass and inertial mass, which in specific electromagnetic conditions can be reduced, nullified, negated, and increased. This means that gravitational forces can be reduced, nullified, inverted, and intensified by means of electromagnetic fields. Such control of gravitational interaction can have a lot of practical applications. For example, a new spacecraft concept arises from the possibility of the electromagnetic control of gravitational mass.