Understanding Electromagnetic Waves

[Ian Baughman]

So I know that EM waves travel perpendicular to the electric and magnetic fields which are also perpendicular to each other. What I'm having difficulty understanding is since light is an EM wave and can travel through the vacuum of space, does that imply that everywhere in the universe there is an electric and magnetic field? It would seem, according to this, if we could find a vacuum where no such fields existed then light would not be able to travel through it.

 

[Vanadium 50]

If the fields are zero before light travels through it it does not imply that the fields are zero when light is traveling through it.

The road outside my house has no cars on it at the moment, but that doesn't mean cars can't drive down it.

 

[PeroK]

So I know that EM waves travel perpendicular to the electric and magnetic fields which are also perpendicular to each other. What I'm having difficulty understanding is since light is an EM wave and can travel through the vacuum of space, does that imply that everywhere in the universe there is an electric and magnetic field? It would seem, according to this, if we could find a vacuum where no such fields existed then light would not be able to travel through it.

Light (the EM wave) is the electric and magnetic fields!