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A collection of some classic Lemmy memes for your enjoyment
Whenever any of this comes up I remember that physics professor's speech on first day of quantum mechanics that got viral:
“Nobody understands 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.
I'm so good at not understanding stuff. My time has come.
Quantum mechanics is illogical and stuff that happens makes no sense but can be recrcreated through experimentation....as long as you don't look at it.
The end
Quantum mechanics is extremely logical - we understand the math extremely well, and the math describes reality better than any other theory.
It is, however, not intuitive.
I was just being cheeky
I'd say we understand quantum mechanics better than most things.
We know more about the behaviour of an electron than we know about the oceans, the Earth, the sun, the weather, the stock market, the human body, prime numbers, and so on.
We generally have a grasp of "why" for that stuff though, even if the whole picture is currently hidden or too complex.
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, that's a property of it being an electron. They have a spin vector (the arrow shown) and whether it is in the same direction or opposite 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 wouldn't 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 referring to when they say "no one understands QM", we know it is the case, we can measure it and predict it, but it makes no fucking sense.
I recall a Richard Feynman video where the interviewer asks him to explain how magnets work.
His answer amounts to "I can't explain that to you because if I gave you an accurate answer it would be too technical for it to make sense to you, and if I simplified it to the extent that you could understand, it would no longer be a meaningful answer."
His point was that we don't understand the interaction between fundamental forces enough to say, if we were to try and answer the question accurately enough.
So, in one sense ICP was right that we don't know how magnets work. But also they were wrong that scientists be lying. They shouldn't have been pissed.
That interview answer always seemed like a cop-out to me. You could make a comparison to gravity to explain how magnetism "just is".
Title-Text: "Of these four forces, there's one we don't really understand." "Is it the weak force or the strong--" "It's gravity."
I expect Feynman’s answer, if he had a whiteboard and unlimited time, would’ve been to dive into Maxwell’s equations.
With that in mind, his answer makes complete sense. Good luck explaining coupled PDEs to people who aren’t mathy in a few sentences without visual aid. The analogy to the gravitational force isn’t on point; there’s a lot more to be said about how magnets tie to into E&M more broadly, compared to gravity.
Though you’re absolutely right that once you get deep enough into any topic in physics that the answer to “why?” inevitably becomes “it just be like that”.
The analogy to the gravitational force isn’t on point; there’s a lot more to be said about how magnets tie to into E&M more broadly, compared to gravity.
Yeah, a proper answer would need to dive into how it relates to electricity for sure
I think OP's meme illustrates Feynman's point very well; there comes a stage where if the number of incorrect statements in your explanation outnumber the the correct ones, it's no longer a meaningful explanation.
Yeah, "spin" was a stupid thing to call it. We have a nice, hard definition of what "spin" is on a macro scale. Why take a complex property of matter that we don't have a name for, and give it the same name as a fairly common, easy-to-understand phenomenon? Extraordinarily smart people being idiots, honestly.
Imagine a woman in hot pants with thighs like a Robert Crumb dream woman.
I don't know if it helps with this problem though.
NoU Imagine a cactus eating a deer.
That's a challenging wank.
(RIP Sean Lock)
Sounds like a class with an attribute called spin.
It does however also have repercussions that are inline with it being a sphere that is spinning.
The universe is a digital simulation confirmed
The memory required to track all these particles was insane, so we just made a wave of where they were most likely to be and picked a random spot when the exact location was needed. 🤷
Right-hand rule bitches!
Is more like a feeling
electrons be vibin
A ball, however tiny, has 3 dimensions, it has a surface that moves around a mathematical point at the center of the sphere.
A point of zero dimensions has no diameter nor perimeter, no surface with which to spin. Yet when influenced by a magnetic field, a point-like indivisible particle behaves as if it does spin.
As Chief Brody might say, we're gonna need a bigger math!
How about imaginary numbers and the complex plane?
Now add the Uncertainty Principle, just for shits 'n' giggles!
Probability space! Probability amplitudes and polarizations!
The way I understood it (probably wrong): imagine if a point like thing, but is actually a wave, hits something else. It will leave a trace on the detector curving in a certain direction. This is interpreted as angular momentum aka spin.
