4

EM wave phenomenon is usually described as "changing electric field creates changing magnetic field which creates a changing electric field etc."

But fields of a uniformly moving (not accelerating) charge also change, and as far as I can see, all the second-order derivatives in time and space required by the wave equation are in place (because of the 1/r^2 dependence).

So, why doesn't the field of a uniformly moving charge create EM waves all by itself, because of all the second-order derivatives? It seems to me that mathematics requires it.

Volker Siegel
  • 3,996
Vitaly Korzhik
  • 127

1 Answers1

1

A uniformly moving charge creates electromagnetic waves. But the electric and magnetic field contain only velocity dependent terms. If it's accelerating, then the field terms contain acceleration term also and in addition to the energy stored in the fields, there will be radiation also which causes considerable decrease in the energy stored in the fields.

In your case, there is electromagnetic wave. The energy will be then stored in the fields as there is no radiation.

UKH
  • 5,021