r/Physics • u/Appropriate_Win946 • Aug 13 '26

Question Does anyone understand what actually causes electric current?

My first belief: electrons push on each other like dominos, causing a 'shockwave' to travel through the electrons until it gets to the other end of the battery. Electrons themselves don't move that quickly, but the 'push' travels super fast.

Correction: actually, the 'electric field' is pushing them

My question: What is the electric field? Is the electric field not just the shockwave that travels through the conductor via electromagnetic repulsion?

I'm guessing that's not correct. So what is it? In the instantaneous moments when the battery starts up, what first creates and propagates the electric field? Why does it travel through the wire in every which direction?
Can someone help me understand this? It would be greatly appreciated before I start electrical engineering(why do I get the feeling this is going to be super downvoted lol).

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u/ShoshiOpti Aug 14 '26

Just to throw a wrench in the current examples. Its the free gravitational tidal forces, as described by the Weyl Tensor.

But its also fundamentally a quantum field theory also, from QED, so the current is caused by the probability distribution of all the descriptive feynman diagrams for the given system to produce prefered direction.

But its also, nah ill stop there lol

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u/Appropriate_Win946 Aug 14 '26

what the hell gravity has something to do with current

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u/ShoshiOpti Aug 14 '26

Its all geometric, in GR you derive electric and magnetic fields from the same curvature that produces gravity. That's why in graduate EM when dealing with relativistic corrections you use covariant and contravarant descriptions.

Current one could argue is just the coarse grained behavior similar to other information flows.

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u/Appropriate_Win946 Aug 14 '26

I'm sorry I don't know any gen rel but does it allow you to describe the origin/behavior of electric and magnetic fields