weirdThis is the hardest concept to understand in physics
Whenever any of this comes up I remember that physics professor’s speech on first day of quantum mechanics that got viral:
“Nobody understand quantum mechanics. The people who came up with it don’t understand it. I will do my best so that by the end of this course you don’t understand it either, and so you can got out to the world and spread our ignorance.”
Or something to that effect.
Whenever this picture comes up I remember that it’s wrong - both electrons on it have the same spin, one is just rotated 180°, but it says +½ for one and -½ for the other, is like a part of the joke?
All electrons have spin 1/2, thats a property of it being an electron. They have a spin vector (the arrow shown) and whether is is in the same direction or oposite direction to the magnetic field it’s in determines where it is plus or minus.
Now you might think “but what if it is not entirely aligned with the field, then it wouldnt be 1/2”, which is true, on aggregate for large numbers of electrons, but if you ever look at a single electron its spin will either be “up” or “down” never any other orientation.
This is the kind of thing people are refering to when then say “no one understands QM”, we know it is the case, we can measure it and predict it, but it makes no fucking sense.
That makes sence though, thanks for clearing that up
I think where the sense starts to fall through is in remembering that it’s not a ball though. It’s a wave, and the spin only in one direction when interacting with something else, otherwise it’s akin to three parts spinning clockwise, and one part spinning counter-clockwise. 🫠
Ah much better, thank you