Richard Feynman Magnets

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Strong rec aunty_helen · 2020-07 · on “Bohr–van Leeuwen theorem – magnetism in solids is a quantum mechanical effect”

[this video] Richard Feynman explaining magnets is one of the best layman explainers I've seen (in between the ranting). I honestly didn't understand why magnets worked and found this on a late night youtube binge. (But don't search youtube for anything related to magnets, you end up amongst the perpetual motion nuts) Edit: Just to be clear with this video (it had been a while since I last watched it), he doesn't 'explain' magnets as much as he hints at the concepts involved. I already knew about the spins being lined up etc but it was the "you can't put your hand through the chair" comment that gave me the eureka moment.

Recommends keldaris · 2020-04 · on “Ask HN: What scientific phenomenon do you wish someone would explain better?”

I'm a physicist specifically working with magnetic systems, but I have very little pre-graduate teaching experience, so take this attempt to answer the question with a grain of salt. The reason some people regard Faraday's original explanation of the eponymous law (it is worth noting that at the time it was widely regarded as inadequate and handwavy) as illuminating is because Faraday visualized his "lines of force" as literal chains of polarized particles in a dielectric medium, thereby providing a seemingly mechanistic local explanation of the observed phenomena. Not much of this mindset survived Maxwell's theoretical program and it has very little to do with how we regard magnetism today.

Recommends rimunroe · 2020-07 · on “Neutrino Particles May Be a Link to the Dark Sector”

I appreciate it. You're absolutely right about how exciting it is to be able to share explanations with people. This is a video of Feynman's answer to an interviewer asking about what and why you feel something when you put two magnets together [this video] . It's a great description of the problems inherent to explaining this sort of thing to people. (Also, if anyone knows a video/essay/talk along these lines by a less sexist person, I'd love a link.)

Recommends ramraj07 · 2025-04 · on “I should have loved biology too”

I don't know if just going to nature is sufficient to get fascinated with biology. In my opinion it takes a fundamental reset in how you think about anything you see. Humans while smart have obviously had to learn to "ignore" thinking about how things work. You don't think too hard about how anything works really. I mean at a cursory level sure, but by vastly different interpretations of the word "cursory", you can change your thirst to know how things you see work at more and more fundamental levels. You don't need to go into nature to get this curiosity except for the possibility that it makes you more meditative. You can look at your arm and think what the hell happens in there at a molec

Cites Luc · 2014-08 · on “Questions about Nasa's space drive answered”

I'd really like the source for that quote, because it's dumb for obvious reasons, and I don't know Feynman to be dumb. In fact he said pretty much the opposite to the interviewer asking about magnets in this well known video: [this video]

Cites AndrewOMartin · 2014-09 · on “Why Question Answering Is Hard”

Also there's the problem of context. When someone asks you a question you generally know what kind of answer they expect. In this classic example from Richard Feynman [1] the answer to "Why is Aunt Minnie in the hospital" can be "She broke her hip", "She slipped on the ice and broke her hip", "An ambulance took her there", "Because her husband is concerned for her well being". What's interesting about the Watson approach is that, by taking intelligently composed web pages as input (as opposed to randomly generated texts, or an arbitrary list of atomic facts) the context is already "baked in". Put another way, people make web pages with sentences like "Aunt Minnie is in the hospital because s

Cites iaw · 2014-12 · on “Study finds possible alternative explanation for dark energy”

I'm a little confused. If I understood the article correctly the argument is that the rate of expansion isn't increasing but staying constant while the rate time passes is slowing. Given that the rate of expansion is a measure of distance over time wouldn't the net effect be identical? I guess the argument is that dark energy is in fact a manifestation of the physical rules of our universe, but in the end doesn't that violate the laws of energy conservation? Effectively if we observe acceleration of distant parts of the galaxy due to present time traveling slower relative to historic, where does the energy that causes the acceleration come from? This is reminiscent of Feynman's explanation a

Cites darkmighty · 2015-02 · on “Ask HN: What do you wish you had known before you turned 40?”

Tip: Extract useful information from people's mistakes, and show it to them. They'll love it (and it's really fun!). (It's a bit like when you ask a smart physicist a silly question instead of telling you're wrong he'll make the most out of it) Examples: [this video] [LINK]