Is the electromagnetic field singular or multiple independent fields?

[csmcmillion]

When I studied EM we always treated EM fields as being "individual" autonomous fields generated either from the separation of charges or induced by other phenomena. However, I'm reading that modern physics is treating the zero-point energy as fluctuations in THE EM field. Susskind clearly states that this EM field exists absent any charges, and is simple a characteristic of empty space.

Am I missing something here?

 

[Dale]

I think you are reading way too much into a preposition. It is possible to have electric and magnetic fields in the absence of charges. These are known as vacuum solutions to Maxwells equations, and take the form of EM waves. Whether you use one preposition for vacuum solutions and another preposition for non-vacuum solutions is not terribly important.

 

[vanhees71]

Even in classical physics there's one and only one electromagnetic field (according to Maxwell's theory as a classical relativistic field theory). This field can have many specific forms dependent on the charges and currents.