A charge here creates scalar (Lorenz) potential V everywhere.
A moving charge here creates vector (Lorenz) potential A everywhere.
Potentials propagate at the speed of light, and this gives the answer: when you close the switch an EM disturbance is created, it propagates to the light and "switch it on".
(It's all fields until you remove them. See Liénard-Wiechert potential, for example in an Atoms & Sporks video or in Wiki)
Maybe I'm an idiot but I really don't see how this interpretation removes any of the fields. And I looked at the Liénard-Wiechert potential - it's defined in terms of vector fields. We're still talking about the propagations of fields, through empty space.
Depends what you mean by fields, when people say "energy is in the fields" they mean in fact "energy is in vacuum", and with Carpenter's interpretation, V,A are mathematical fields but vacuum plays no role at all, it's just the place where they propagate.
Liénard-Wiechert showed that you could completely remove them. In Wiki the formulas give the potentials produced, because everyone thinks in terms of potentials/E,B, but you can just compute the forces exerted on particles by each other in this way and stop here.
In this way, you get the dynamic version of Coulomb force (which is equivalent to Maxwell's equation), and where vacuum plays absolutely no role (except retarding forces), there is no need to define a potential in vacuum.
If you take this to be "the truth" then the concept of light is this: accelerated charges create forces on charges which slowly decrease with distance.
The Casimir effect is a pretty peculiar beast. =)
But one thing to consider is that vacuum is not void.
Indeed. And I don't mean to be unfair by bringing it up. The Casimir Effect is not something predicted by Classical ED even if it has thematic similarities to aether ideas from Maxwell. I guess it just shows they had a shadow of vision of the future.
What I'm driving at is that in neither Classical ED, nor Einsteinian QM, nor in modern QFT is the vacuum considered to be a void that can't have energy in it. Thus, I don't really respond to philosophical arguments that suppose the vacuum can't have energy going through it 'just because' - whether it's energy-less photons or these "signals" (as Atom & Sporks says in the video recommended video by Naej) from one charge to another that are very totally not energy propagating in a field, just, 'remote action effects.'
The concepts have to change with the theory you use, and the theory with what you're doing.
If you want the current conception of vacuum, then it's a (local?) minimum of energy, whose energy (named dark energy) is driving an exponential-like acceleration of the size of the universe. And Casimir effect is because you can go below the vacuum in energy density.
If it's only a local minimum then it can decay, and it's one popular theory of what happened at the initiation of the Big Bang.
bsfeechannel: so you reject a theorem with 19th century philosophy. Ok.
Also I said many times that both Poynting's and Carpenter's view are correct, so if you don't see a difference with what Derek said, then you don't see much.
adx: if you follow Poynting then copper wires are the low-frequency equivalent of light fiber, a transformer is impedance matching, and a resistor is a low-frequency black-body.
For acoustic waves, half the energy is in the pressure, and half in the velocity (much like in light, half is in E, half is in B).