Understanding Electromagnetic Waves

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Electromagnetic (EM) waves, including light, travel perpendicular to both electric and magnetic fields, which are also perpendicular to each other. The discussion raises the question of whether light's ability to travel through a vacuum implies the existence of electric and magnetic fields everywhere in the universe. It suggests that if a vacuum were devoid of these fields, light would not be able to propagate. The analogy of a road without cars illustrates that the absence of fields does not preclude their existence during light's travel. Ultimately, light itself embodies the electric and magnetic fields, reinforcing their integral relationship.
Ian Baughman
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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.
 
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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.
 
Ian Baughman said:
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!
 

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