Why do magnetic forces exist?

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Not necessarily their purpose. Just what is happening that is creating the force and how does this force interact between fields?

For example, I get how heat transfer works. Conduction and convection make sense to me because two pieces of matter interact with each other and transfer energy. Cool.

I know it’s not a particle so I guess it’s a wave? A wave of what?

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> Conduction and convection make sense to me because two pieces of matter interact with each other and transfer energy. Cool.

But they interact through precisely the same means as magnetic interaction does.

Your mistake is in thinking of particles as something separate from forces, and in thinking of “interaction” as “touching”. These concepts don’t really make sense at the scale of subatomic particles.

In quantum mechanics, a “particle” is just a “bump” in the physical fields that make up reality. If the fields are an ocean, the particles are the waves in that ocean: made from it and fundamentally tied to it in an inextricable way. From that perspective, it’s not odd at all that two particles interact through a field, because it’s actually just the field itself evolving (because the particles themselves are made from and are part of the field itself). It doesn’t even make sense to talk about a wave separately from the ocean in which it exists, because the properties of the wave *are* the properties of the water in a particular configuration.

Moreover, particles aren’t points. When you think about conduction or convection, you’re probably picturing a bunch of little marbles bumping into each other. But in the full treatment, every particle is a smeared-out “blob” that extends out to infinity (or at least, very far, depending on how you mix QM and relativity). The particles in my body are, in that sense, currently “touching” the particles in yours, in the sense that the smeared-out-blobs of me overlap with the smeared-out-blobs of you. As particles get closer, this overlap grows, but there’s no sharp boundary. There’s no notion of touching: just of greater or lesser overlap. And when they interact, they interact *because their underlying representations in physical fields happen to overlap*.

I’m assuming you’ve been taught that electricity is the flow of electrons through a conductive surface and that magnetism is a field created by ferromagnetic materials.

This “lies to children” explanation for these two phenomena obscures what’s really going on.

There is one electromagnetic force, caused by atomic alignment, momentum, and differential atomic charges.

Essentially, it’s most similar to the relationship between gravity and centripetal force — both follow the right hand rule where there is force applied at right angles to the direction of movement.

However, with electricity, this “force” isn’t actually electrons moving from one atom to the next, it’s just a transfer of their kinetic energy. When there are enough transfers that are aligned (so it’s easiest for energy to “flow” in a certain direction, this extends out in an energy field that is just as strong in a vacuum as it is in a large piece of metal. The field decays according to the inverse square law — so the more energy “flowing” in the core, the further away the field will reach.

So you can think of magnetism as being like if two streams of water are running side by side, they will easily join up and then be hard to separate, and if they’re flowing in opposite directions, they will bounce off each other. But the “streams” are not electrons, they’re electromagnetic energy “wavicles” interfering with the space/time relationship of any other particles in the area, according to the inverse square law.

Or, back to the gravity equivalence: if you spin a bucket of water, the force of the spin forces all the water to try to move at right angles to the movement, overcoming gravitational force. Likewise, forcing directional charge in a large number of atoms that can easily give up the energy stored in their outer shell overcomes electromagnetic stasis, and the result is the magnetic field.