The author has made revisions to the classical electromagnetic theory. The solution of Maxwell’s equation has been reinterpreted. It is believed that advanced waves exist, radiation does not overflow the universe, and the Poynting vector of electromagnetic waves is reactive power. The electric and magnetic fields in the far field have a 90 degree phase difference. Transmission line problems are often solved using circuit methods. The voltage and current are in phase. The results of calculating the electric and magnetic fields according to Maxwell’s equations are the same. According to the author’s revised electromagnetic theory, there are two types of electric fields on transmission lines: electrostatic field and induced electric field. The electrostatic field is in phase with the current on the transmission line. The induced electric field lags 90 degrees behind the current. This is consistent with a simple circuit. Therefore, for transmission lines, the author’s theory contradicts the conclusions of existing textbooks. Transmission lines are a good example of distinguishing between two theories. The author also proposed a method for experimental verification.

Maxwell’s equation, Poynting, retarded wave, advanced wave, retarded potential, advanced potential, antenna, transformer, electromagnetic wave, electromagnetic field, energy flow, quasi-static state, transmission line