Magneto Goes Back to School

Nate asked me a couple questions about my last post, which I thought I would take a minute to answer.

Can you give a more detailed explanation of magnetic fields with a non-zero second derivative? Can we generate them in a lab? Do they occur naturally?
Yeah, I glossed over that a bit.  The idea is that the field can't just be changing – the rate of change must change.  As complicated as that sounds, it's actually really easy to do.  If you hold a magnet in your hand and move it around, you're making a magnetic field with non-zero second derivative.  However, if you wanted to generate even visible light (let alone the deadly ionizing radiation I was talking about) you'd need to move the magnet up and down on the order of quadrillions of times per second.  Who knows how quickly Magneto can change his fields, but maybe with a bit of practice he could manage it.

If I have an electromagnet and I vary the input power, would that produce photons?
This may seen like a more reasonable way to get the fast variation that I'm talking about, but now you'll run into the problem of inductance.  Electromagnets create magnetic fields from electric current, but when you increase the current in an electromagnet, the magnetic field will also increase.  This creates an electric field which opposes the increasing current, slowing things down.  The same happens when the current decreases, so you still may not be able to get the speed you need.

And are the photons being produced, or just redirected?
I think it's fine to say that they are being produced, but this is getting into an area of physics I don't know much about yet.  Photons are quantum mechanical particles, while electromagnetic fields (at least the sort I'm talking about) are classical approximations of whatever is studied in quantum field theory.  Technically, I'm not sure if it's ever correct to say that a photon is 'redirected,' but they can be absorbed and re-emitted in a different direction.

Thanks for more great questions, Nate!  Everyone else should feel free to send me their own – part of the purpose of this blog is to educate, so don't feel afraid to ask even the simplest questions.