From my understanding, a moving charge produces a magnetic field, and a non-moving charge does not produce a magnetic field. However, I'm wondering if there's a way for a magnetic field to be produced without involving any charged particle at all. I was thinking about a bar magnet, or some other permanent magnet made of ferromagnetic material, but if the electrons within the material interact with each other, then would that count as a charge? Thanks for any help!
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Electrons have an intrinsic magnetic moment, which generates a magnetic field. This magnetic moment is unrelated to any motion, and it is a consequence of the electron's spin (which isn't a movement).
Peter Mortensen
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Juan Perez
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Perhaps magnetic monopoles exist... Many theories suggest that they should exist, but they might be enormously rare.
If they do exist then they would produce a magnetic field that had non-zero divergence. The magnetic fields generated by moving electrons obey Gauss's law: $\mathbf{\nabla}\cdot\mathbf{B}=0$ But the field generated by a monopole would have $\mathbf{\nabla}\cdot\mathbf{B}\propto \rho$ the density of magnetic charge.
Magnetic monopoles would be a form of magnetism that was entirely unrelated to the motion of particles with electric charge. They are theoretical but many physicists think that they probably do exist, but are too massive to make in particle colliders, and to rare for natural ones to ever be detected by luck.
James K
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The magnetic field at a point/time is generated by currents, and time-varying currents on the past light-cone. That's it. A dipole is just a current in a small loop.
The time varying current may also generate an electric field that looks like it's inducing the magnetic field, but it's not.
JEB
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