3 ms·

Feynman explains magnets - https://www.youtube.com/watch?v=Q1lL-hXO27Q https://www.youtube.com/watch?v=Q1lL-hXO27Q

by c22 4y ago

hilbert42 4y ago
I suppose I was primed to reply to this HN question because I'd seen that Feynman video previously, actually I downloaded it ages ago during a similar discussion on the subject. I think I've seen just about every Feynman video multiple times and despite his remarkable Tour de Force answer here I think it's the worst of his explanations. Nevertheless, I know why he answered this way (moreover, for Feynman, it was likely the most diplomatic answer he could have given in the circumstances). I understand what Feynman is getting at which is that it's essentially impossible to explain or convey physical ideas that have no easy or parallel (understandable) real-world analogues that we're familiar with except, say, to those trained in physics and who've also training in abstract mathematical concepts. When Grandma asks why her fridge magnets stick to the fridge it's rather pointless to answer "Now Grandma, take a comfortable seat, first I have to teach you a little about a thing called QED – Quantum Electrodynamics and to do that we may have to deviate off into learning a bit of math called Yang-Mills formalism." Clearly, anyone who knows a modicum about this subject knows the problem and can understand why Feynman was frustrated and thus gave that answer. Anyway, that definitely wasn't what I was on about in my first reply. What I was referring to or at least implying is that we do not understand why the laws of physics upon which QED/QFT are built are the way they are - that is we know very well how the laws interact and that QFT works remarkably well but not the underlying reasons for why it does. These of course are the fundamental force interactions which I alluded to in my reply that mentioned the weak force. In his reply aristofun sums it up most succinctly when he refers interaction between the fundamental forces. I've thought for some time that when asked a question like this about fridge magnets or similar, physicists should bypass all the intermediate and confusing dross and cut to the core and say something to the effect "it looks easy but it's a difficult question, it hinges fundamentally on the on the interaction between the fundamental forces which we think are irreducible laws of nature but we are not completely certain about that", ...and from there fill in any other necessary info. If I'd been told this from very early on it would have made my understanding of the subject very much easier.

Feynman explains magnets - https://www.youtube.com/watch?v=Q1lL-hXO27Q https://www.youtube.com/watch?v=Q1lL-hXO27Q

by c22 4y ago

Feynman explains magnets - https://www.youtube.com/watch?v=Q1lL-hXO27Q https://www.youtube.com/watch?v=Q1lL-hXO27Q

I suppose I was primed to reply to this HN question because I'd seen that Feynman video previously, actually I downloaded it ages ago during a similar discussion on the subject. I think I've seen just about every Feynman video multiple times and despite his remarkable Tour de Force answer here I think it's the worst of his explanations. Nevertheless, I know why he answered this way (moreover, for Feynman, it was likely the most diplomatic answer he could have given in the circumstances). I understand what Feynman is getting at which is that it's essentially impossible to explain or convey physical ideas that have no easy or parallel (understandable) real-world analogues that we're familiar with except, say, to those trained in physics and who've also training in abstract mathematical concepts. When Grandma asks why her fridge magnets stick to the fridge it's rather pointless to answer "Now Grandma, take a comfortable seat, first I have to teach you a little about a thing called QED – Quantum Electrodynamics and to do that we may have to deviate off into learning a bit of math called Yang-Mills formalism." Clearly, anyone who knows a modicum about this subject knows the problem and can understand why Feynman was frustrated and thus gave that answer. Anyway, that definitely wasn't what I was on about in my first reply. What I was referring to or at least implying is that we do not understand why the laws of physics upon which QED/QFT are built are the way they are - that is we know very well how the laws interact and that QFT works remarkably well but not the underlying reasons for why it does. These of course are the fundamental force interactions which I alluded to in my reply that mentioned the weak force. In his reply aristofun sums it up most succinctly when he refers interaction between the fundamental forces. I've thought for some time that when asked a question like this about fridge magnets or similar, physicists should bypass all the intermediate and confusing dross and cut to the core and say something to the effect "it looks easy but it's a difficult question, it hinges fundamentally on the on the interaction between the fundamental forces which we think are irreducible laws of nature but we are not completely certain about that", ...and from there fill in any other necessary info. If I'd been told this from very early on it would have made my understanding of the subject very much easier.