<The Detail of This Chapter.pdf>
The key actor of classical field:
light (electromagnetic wave, not photon) and the velocity of light transmit in vacuum.
The basic intention of classical field theory is to describe the electromagnetic phenomenon of macrocosmos, not the gravitation phenomenon.
1.At first, the electromagnetic phenomenon of macrocosmos can be viewed as classical mechanics movement of charges (particle). (ref)
1.1.history of discovery
1785~1799, Coulomb: the force between charges
1820~1827, Ampere: current-magnetic field
1832~1855, Faraday: magnetic field-current
1861~1864, Maxwell: Maxwell equations
the retarded potentials