  Physical fields, such as gravity and electromagnetic field, are interpreted
as results from rearrangement of vacuum particles to get the equilibrium of net
charge density and net mass density in 4-dimensional complex space. Then, both
fields should interact to each other in that physical interaction is considered
as a field-to-field interaction. Hence, Mass-Charge interaction is introduced
with primitive-virtual negative charge defined for the mass. With the concept
of Mass-Charge interaction electric equilibrium of the earth is discussed,
especially about the electric field and magnetic field of the earth. For
unsettled phenomena related with the earth's gravity, such as antigravity
phenomenon, gravity anomalies during the solar eclipses, the connection between
geomagnetic storms and earthquakes, etc., possible explanations are discussed.
