- #1
nonequilibrium
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It seems really basic, like a remark which probably everyone asks himself when first coming upon electromagnetism, but I can't see the error in my reasoning, which leads to violating the principle of relativity:
Imagine two protons passing each other by, each with a speed v, opposite to each other, but one is flying just higher so that they don't collide. As the bottom one passes beneath the top one and they're at their closest point, the bottom one is creating a magnetic field that is pushing the top one away (well, the resulting Lorentz force is, anyway). (note: there is also an electric force)
Now imagine the same experiment, but viewed from an inertial reference frame with a speed v flying in the direction of the bottom proton. Now, as they pass at the same point, the bottom proton is not creating a magnetic field because in this reference frame it is standing still. So there is no magnetic force pushing the top one away, only the electric force, which hasn't changed.
Contradiction.
Much obliged,
mr. vodka
Imagine two protons passing each other by, each with a speed v, opposite to each other, but one is flying just higher so that they don't collide. As the bottom one passes beneath the top one and they're at their closest point, the bottom one is creating a magnetic field that is pushing the top one away (well, the resulting Lorentz force is, anyway). (note: there is also an electric force)
Now imagine the same experiment, but viewed from an inertial reference frame with a speed v flying in the direction of the bottom proton. Now, as they pass at the same point, the bottom proton is not creating a magnetic field because in this reference frame it is standing still. So there is no magnetic force pushing the top one away, only the electric force, which hasn't changed.
Contradiction.
Much obliged,
mr. vodka