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I keep hearing everywhere that magnetism and electromagnetism are different but is seems to me that when a current is moving and it creates a "magnetic field", it is just electrons repulsing other electrons and attracting protons, isn't that electromagnetism?

In a natural magnet, are not all electrons aligned pointing to the same side so that other electrons are repelled? If so this seems like regular electromagnetism to me...

Please clarify, I am a physics rookie.

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  • $\begingroup$ Electricity and Magnetism seemed like 2 distinct forces a while back, but we now know that they are really the same force manifesting itself as 2 seemingly distinct forces. That force is the Electromagnetic force. $\endgroup$
    – PhotonBoom
    Commented Dec 8, 2014 at 17:46

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Your instincts are spot on. While it’s still common for people to refer to electricity and magnetism as different phenomena, they’ve been formally unified since Maxwell’s 1873 paper on the subject, and they were known to be intimately related for decades before that through Faraday’s work among others. “Electromagnetism” covers all of the behavior of charges whether they’re at rest (static electricity) or in motion relative to an observer and/or each other (magnetism).

Like you said, it’s all just electrons repelling other electrons and attracting protons. The neat thing about electrons in motion (which we still refer to as magnetism to make it clear that we’re talking about moving electrons) is that it’s special relativity in practice. In our daily lives we don’t typically get to see the effect of length contraction that Einstein predicted for moving bodies, but we do get to see its effect with currents and magnetism because electrons move so fast: a magnet is applied special relativity in the palm of your hand! (Be careful about trying to contain a fusion reaction with it though, that’s tricky business ;)

Natural magnetism and ferromagnetism is a bit more complicated, and involves quantum mechanics, but you have the gist of it: when regions (called “domains”) within a material can be forced to retain a predominance of electron spin alignments around one direction of an axis more than the other, the material is said to have magnetic polarization, which can produce powerful effects. But even in our strongest magnets, only a tiny fraction of the electrons in the material are spinning more in one direction around the axis of polarization than the other – if we could somehow get –all- of those electrons aligned to spin in one direction the forces would be almost inconceivably powerful...

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  • $\begingroup$ Thank you very much for a beautiful and thorough answer. I can now sleep at night knowing that magnetism is not a mythical force that differentiates much from the regular interaction of particles in a current. $\endgroup$
    – reddead
    Commented Dec 9, 2014 at 17:02
  • $\begingroup$ My pleasure yaou - I'm glad that I could spare you the nights of unrest about this one, but since you certainly think like a physicist, I'm sure there will be many more questions to keep you up late contemplating! $\endgroup$
    – Thomas M
    Commented Dec 10, 2014 at 4:32
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All magnetism originates from movement of charge not movement of current as you mention. Whether it is arising from flow of charge positive or negative ( current ). Spin alignment's as in a ferromagnetic. Spin is again charge in motion that is rotation.

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