As we know through experiment, the magnetic force around a current carrying wire always points in the same direction given the direction of current, and this direction is described with the ‘right hand rule.’ What is it about the universe that has this ‘preference’ for this, and only this, direction?
Or from a mathematics perspective, why are our electromagnetic vector coordinates the way they are, and not the other way around? It seems the direction of fields is axiomatic to the equations, and something we tack on at the end after calculating magnitudes. For instance, “we just used ampere’s law to calculate the force at this distance from the wire, now to know the direction, let’s use the right hand rule.” Nowhere in the math does it say that the direction is a necessity.
It seems to just be an observed fact, and we have to include this fact in our equations. But this fact is not derived from the equations. For context, I understand that the electromagnetic equations can be solved with either a right or left convention. My question does not pertain to this convention, but the underlying nature of the universe and its ‘preference’ to follow the same direction every time given a direction of current. If it’s said the angular momentum of the vector causes this direction, then still it remains why this direction and not the other?
It all seems so asymmetric and arbitrary.
In: Physics
It’s not a matter of sign convention. The right hand rule works the same if you swap conventional positive current with electron flow, and swap the force sensing particles charge from positive to negative.
What OP is asking is why the system behaves in the way we observe. For example, if you take two parallel wires with currents of the same sign traveling through them in the same direction, the magnetic force will cause the wires to be attracted to each other. If the currents are traveling in opposite directions then the wires will be repelled from each other. Why doesn’t the reverse occur?
IIRC the answer has something to do with relativity and how with electrostatic forces opposite charges attract.
Edit: This veritasium video https://youtu.be/1TKSfAkWWN0?si=IqvPYGrPhgzzz_lA
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