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The Feynman Lectures on Physics (1961-1964)
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- colmmacc 9mo agoLesser known but possibly more relevant to most HN readers are Feynman's lectures on computation - https://theswissbay.ch/pdf/Gentoomen%20Library/Extra/Richard_P._Feynman-Feynman_Lectures_on_Computation__-Addison-Wesley%281996%29.pdf https://theswissbay.ch/pdf/Gentoomen%20Library/Extra/Richard... . There's some really great explanations in there of computability, information theory, entropy, thermodynamics, and more. Very little of it is now out-dated.
- jesuslop 9mo agoInteresting, he also talks about quantum computing (a first?): p. 191, "We now go on to consider how such a computer can also be built using the laws of quantum mechanics. We are going to write a Hamiltonian, for a system of interacting parts, which will behave in the same way as a large system in serving as a universal computer." p. 196: "In general, in quantum mechanics, the outgoing state at time t is eⁱᴴᵗ Ψᵢₙ where Ψᵢₙ is the input state, for a system with Hamiltonian H. To try to find, for a given special time t, the Hamiltonian which will produce M = eⁱᴴᵗ when M is such a product of non-commuting matrices, from some simple property of the matrices themselves, appears to be very difficult. We realize, however, that at any particular time, if we expand eⁱᴴᵗ out (as 1 + iHt − H²t²⁄2 + …) we'll find the operator H operating an innumerable arbitrary number of times — once, twice, three times, and so forth — and the total state is generated by a superposition of these possibilities. This suggests that we can solve this problem of the composition of these A’s in the following way..."
- dgfl 9mo agoFeynman is indeed often quoted among the first people to propose the idea of a quantum computer! This talk he gave in ‘81 is among the earliest discussion of why a quantum universe requires a quantum computer to be simulated [1]: > Can a quantum system be probabilisticaUy simulated by a classical (probabilistic, I'd assume) universal computer? In other words, a computer which will give the same probabilities as the quantum system does. If you take the computer to be the classical kind I've described so far, (not the quantum kind described in the last section) and there're no changes in any laws, and there's no hocus-pocus, the answer is certainly, No! This is called the hidden-variable problem: it is impossible to represent the results of quantum mechanics with a classical universal device. Another unique lecture is a 1959 one [2] about the potential of nanotechnology (not even a real thing back then). He speaks of directly manipulating atoms and building angstrom-scale engines and microscope with a highly unusual perspective, extremely fascinating for anyone curious about these things and the historical perspective. Even for Feynman’s standards, this was a unique mix of topics and terminology. For context, the structure of DNA has been discovered about 5 years prior, and the first instruments capable of atomic imaging and manipulation are from at least the 80’s. If you’re captivated by this last one as I was, I can also recommend Greg Bear’s novel “Blood Music”. It doesn’t explore the nanotechnology side much, but the main hook is biological cells as computers. Gets very crazy from there on. 1. https://s2.smu.edu/~mitch/class/5395/papers/feynman-quantum-1981.pdf https://s2.smu.edu/~mitch/class/5395/papers/feynman-quantum-... 2. https://www.zyvex.com/nanotech/feynman.html https://www.zyvex.com/nanotech/feynman.html
- anoncow 9mo agoAre there Feynmans today making predictions which we scoff at.
- richardfeynman 9mo agoindeed there are.
- dgfl 9mo ago“There’s plenty of space at the bottom” only really took off in popularity decades later. Feynman’s accomplishments are undeniable, Nobel prize and all, but his celebrity status is given by other aspects of his personality. No Feynman equivalent I can think of is alive today. Perhaps Geoffrey Hinton and his views on the risk of AGI? He’s far from the only one of course.
- jesuslop 9mo agoIBM (atoms) [1989]: https://en.wikipedia.org/wiki/IBM_%28atoms%29 https://en.wikipedia.org/wiki/IBM_%28atoms%29
- WhitneyLand 9mo agoThe quote is not suggesting a quantum computer can’t be simulated classically, it can in fact, just slowly, by keeping track of the quantum state where n qubits is 2^n complex amplitudes. It relates more to the Bell results, that there doesn’t exist a hidden variable system that’s equivalent to QM.
- griffzhowl 9mo agoIf you're into atomic physics and getting a feel for the intricate structure of the basic processes, the best find I had recently is this MIT course by Wolfgang Ketterle. The first lecture is an informal overview, and he gives vivid and detailed descriptions of the phenomena they can create and control now, like why we see different kinds of thing happening at very low temperatures: the atoms are moving past each other so slowly that it gives their wavefunctions time to overlap and interact, using intersecting lasers to create arrays of dimples in the electromagnetic field to draw in and hold single atoms, this kind of thing. It gives a more tangible insight into the quantum aspects of matter that can otherwise seem inscrutable https://www.youtube.com/watch?v=Agu68RGaoWM&list=PLUl4u3cNGP62uOSArqLf4vNLiZtgIRm1K https://www.youtube.com/watch?v=Agu68RGaoWM&list=PLUl4u3cNGP... He also got the Nobel prize in the 90s for making a Bose-Einstein condensate iirc.
- Isamu 9mo agoApropos of Feynman on computing, the story of his time working at Thinking Machines Corp https://longnow.org/ideas/richard-feynman-and-the-connection-machine/ https://longnow.org/ideas/richard-feynman-and-the-connection... “For our first seminar he invited John Hopfield, a friend of his from CalTech, to give us a talk on his scheme for building neural networks. In 1983, studying neural networks was about as fashionable as studying ESP, so some people considered John Hopfield a little bit crazy. Richard was certain he would fit right in at Thinking Machines Corporation.”
- mhh__ 9mo agoThe Feynman lectures are obviously brilliant but think the computation lectures are probably a better display of Feynman's brilliance. It's quite stunning how up to date they are. Although that being said the rough outline of a field is usually worked out almost immediately after a consensus forms that it's "real" so to speak.
- chii 9mo agoThe theory of computation hasn't changed a whole lot since those times - and feynman explains it very well to a laymen audience (which is what makes it great, as it's not filled with jargon).
- mkw5053 9mo agoI was just talking to someone about Feynman's lectures on computation the other day. I really really enjoyed it. That's all.
- CaptainNegative 9mo agoI feel like the section on primality testing with Fermat's test should at least make a shout out to Carmichael numbers and that for some inputs the probability you get a false positive result is 1.
- vmilner 9mo agoUnlike the commercial audio CDs of the lectures the recordings here have the chat before and after the lecture which is fun. My favourite lecture is the standalone "The Principle of Least Action" at https://www.feynmanlectures.caltech.edu/II_19.html https://www.feynmanlectures.caltech.edu/II_19.html Audio: https://www.feynmanlectures.caltech.edu/II_19.html#Ch19-audio https://www.feynmanlectures.caltech.edu/II_19.html#Ch19-audi...
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- ontouchstart 9mo agoThis one is my favorite too. I had the three volumes of hardcover copy. > Later chapters do not depend on the material of this special lecture—which is intended to be for “entertainment” We might say this is the most important chapter in the whole series.
- pm90 9mo agoI have the print version and have been working through them slowly. Funnily enough I didn’t find it very useful when I had physics classes in school/uni since most of those classes were just memorizing equations and solving problems. But now that there is no exams pressure, it makes for such wonderful reading! I think its not just an introduction to physics but to the scientific method itself. Its first principles approach is so different than most physics textbooks.
- rramadass 9mo ago"I have never let my schooling interfere with my education" - Mark Twain
- another_twist 9mo agoSelf study is the best study. Out of all the bloatedness of modern education, one thing that doesnt bother me is the high cost of textbooks. High quality books and a habit of studying yourself enables you to learn high skill disciplines on the cheap. For me, I am currently slogging through Lazlo Lovasz's combinatorics book and another one on Monte Carlo method. Dont know why but its just a good way to pass the time while staying away from the internet and its attention hogging.
- ontouchstart 9mo agoI got a kindle Scribe which can load PDF, HTML and text files via iPhone Kindle App and read offline. Since most pre-1925 books are out of copyright and free on https://gutenberg.org https://gutenberg.org, ACM is open access (https://dl.acm.org/ https://dl.acm.org/) and we have open https://arxiv.org/ https://arxiv.org/, it is the golden age for readers seeking original content. We don’t need bots to read for us. We can live in the mind of human writers.
- muwtyhg 9mo agoAre technical/scientific books from pre-1925 particularly useful for self-learning today? I'd imagine for most disciplines, the knowledge has progressed and possibly changed course since then and it may be more outdated than not.
- rapatel0 9mo agoOne gem if you're interested in semiconductors is the Feynman lecture "There's plenty of room at the bottom." He basically laid out the case for the modern nanotechnology age in 1959 https://web.pa.msu.edu/people/yang/RFeynman_plentySpace.pdf https://web.pa.msu.edu/people/yang/RFeynman_plentySpace.pdf
- evanb 9mo agoI'm using these to teach an intermediate mechanics class, and my only regret is that there are no problems. The flip side is that sometimes Feynman skips over the derivations of certain things, and that makes good assignments ("Fill in the steps between [these assumptions] and [this result]"). Feynman's writing of course is stellar. The order is a bit unusual and not really designed for a "standard" university-level course. I can pick and choose, but I wish I could easily reorder the material.
- madcaptenor 9mo agoThere is a book of exercises, which I've heard of but not looked at myself, titled "Exercises for the Feynman Lectures on Physics". I don't know if that will help you but it might be worth a look.
- evanb 9mo agoI'll try to find it; thanks!
- vmilner 9mo agoLooks like they're here: https://www.feynmanlectures.caltech.edu/info/exercises.html https://www.feynmanlectures.caltech.edu/info/exercises.html https://www.feynmanlectures.caltech.edu/flphandouts.html https://www.feynmanlectures.caltech.edu/flphandouts.html
- mmooss 9mo agoWhat has changed in 60 years, I wonder? If you are teaching this material, what do you have to update and/or contextualize?
- rngfnby 9mo ago[dead]
- rramadass 9mo agoThis is a good question and my initial thought would be Atomic Physics and Cosmology. A book like Modern Atomic Physics by Vasant Natarajan (2015) would be a good place to look - https://www.routledge.com/Modern-Atomic-Physics/Natarajan/p/book/9780367077136 https://www.routledge.com/Modern-Atomic-Physics/Natarajan/p/... The recent book (free) Atomic Physics for Everyone: An Introduction to Atomic Physics, Quantum Mechanics, and Precision Spectroscopy with No College-Level Prerequisites (2025) should also be good for an initial understanding of atomic physics - https://news.ycombinator.com/item?id=46961595 https://news.ycombinator.com/item?id=46961595 Also Wikipedia has a helpful Timeline of fundamental physics discoveries page to browse - https://en.wikipedia.org/wiki/Timeline_of_fundamental_physics_discoveries https://en.wikipedia.org/wiki/Timeline_of_fundamental_physic... Finally, asking Google something like "what is new in physics since feynman lectures", Gemini gave me a helpful summary in its "AI Overview" which you can also try out.
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- delichon 9mo agoPoets say science takes away from the beauty of the stars—mere globs of gas atoms. Nothing is 'mere.' I too can see the stars on a desert night, and feel them. But do I see less or more? The vastness of the heavens stretches my imagination—stuck on this carousel my little eye can catch one-million-year-old light. A vast pattern—of which I am a part—perhaps my stuff was belched from some forgotten star, as one is belching there. Or see them with the greater eye of Palomar, rushing all apart from some common starting point when they were perhaps all together. What is the pattern, or the meaning, or the why? It does not do harm to the mystery to know a little about it. For far more marvelous is the truth than any artists of the past imagined! Why do the poets of the present not speak of it? What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?
- mananaysiempre 9mo agoA footnote for those of the millenial or more recent persuasion: we take the full “vastness of the heavens” as given, as we’ve seen it described pretty confidently all the way back to the science books of our childhood. But cosmology, and frankly the entire field of astrophysics, is strikingly young. The idea that nebulae are in fact whole independent collections of stars, and that the observable universe is large enough to accomodate all of that, is younger than quantum mechanics and relativity both, and only got acceptance after a huge fight. The name “Big Bang” was originally a pejorative used in a similar, later fight. And so on. When Feynman said this, the idea of nebulae as galaxies was younger (~40 years) than the key idea of quarks (confinement/asymptotic freedom) is today (~50 years), and I’m guessing the latter still counts as new and arcane in your mind.
- kmaitreys 9mo agoI feel uncomfortable labelling nebulae as collection of stars. The more appropriate term is stellar nursery if you want to allude to their role in star formation. They themselves are just clouds of gas and dust where protostars have begun to form. Stellar clusters are what you would call a collection of stars. Also on the note of cosmology and astrophysics being strikingly young fields, I think that's fair statement if we consider their modern definitions. Although their core ideas have already been discussed in a lot of ancient civilizations. It was a lot more philosophical and less rooted in science though (except for the observational astronomy, which remains perhaps one of the oldest scientific discipline).
- chadrs 9mo ago"the sham legacy of Richard Feynman" https://www.youtube.com/watch?v=TwKpj2ISQAc https://www.youtube.com/watch?v=TwKpj2ISQAc
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- Brian_K_White 9mo agoThat was rather more interesting than I thought it would be.
- fud101 9mo ago[flagged]
- noosphr 9mo agoWhat's this better stuff?
- fud101 9mo agoShrek for example.
- cindyllm 9mo ago[dead]
- TurdF3rguson 9mo agoI thought you were going to say skibidi toilets.
- Vaslo 9mo agoyt is YouTube?
- rngfnby 9mo agoSo true. How this guy captures the imagination of the English speaking world is astonishing. Sommerfeld Landau Schwinger They mop the floor with Feynman but no one remembers them. Landau, meanwhile had the most comprehensive set of physics book, Sommerfeld the most accessible deep set of physics books. Meanwhile "the Feynman Lectures" burry important details that will derail a train as soon as you leave the safe space of first order approximations. Feynman's lectures are akin to the "everything is a mass on a spring" meme. Actually, nothing is, and the nobilities are everything. To his credit, though, Feynman never intended his lectures to be more than an intro survey class
- karcass 9mo agoMy copy of volume 1 is signed!
- MS007 9mo agoFeynam is my hero. I have Volumes I, II, and III of his red hardbound books. His biography, Surely You're Joking, Mr. Feynman!, is one of my favorites.
- richardfeynman 9mo agoI appreciate it, thanks.
- LightBug1 9mo agoWas funny the first time ...
- richardfeynman 9mo agoThanks for posting this.
- bibimsz 9mo agonot lost on me that the top of hacker news came from 60 years ago. we are entering the period of mourning what was won is n ow lost and the later days once feared are... now here. (the poet called bib)
- SachinnJainn 9mo agoAmazing!
- ncb9094 9mo agoI remember watching these for my JEE (Joint Entrance Examination) of India
- ReptileMan 9mo agoThere is a whole genre of youtube videos with AI generated Feynmann voice based on those lectures. They are of surprisingly high quality.
- tsycho 9mo agoDo you have a link to a good one? I presume the original videos of Feynman are lost, or never existed?
- ReptileMan 9mo agohttps://www.youtube.com/watch?v=83EB1jGJwqE https://www.youtube.com/watch?v=83EB1jGJwqE I found this channel to be ok-ish.
- jonjacky 9mo agoThere are none. It was not routine to make videos in 1961 - 1964. The Feynman Lectures website does have links to recordings of almost every lecture, but no video. BUT there are thousands of photos --- many photos of each lecture, showing Feynman's blackboards. Also, there are videos there of a series of 7 lectures at Cornell in 1964.
- iberator 9mo ago[flagged]
- xorphex 9mo agoYou mean this part? "I adopted the attitude that those bar girls are all bitches, that they aren't worth anything, and all they're in there for is to get you to buy them a drink, and they're not going to give you a goddamn thing; I'm not going to be a gentleman to such worthless bitches, and so on." Great advice! Not misogynistic at all!
- iberator 9mo agoThere is a whole chapter about it, and it's not mysogonic. He addressed the problem of females who simply eat and drink for free EXPLOITING stupid dudes as the default mode of partying. That's why he is hostile to them with I highly recommend reading it. It's not worse than calling someone who exploits drunk women as 'dickhead'. Lastly the word 'bitch' used here is an important part of the particular story where he used it against particular women who scammed him during the confrontation later. Read it as whole
- xorphex 9mo agoI have read the whole chapter, and my criticism is not based on taking a single quote out of context. Your framing reduces women in that environment to a single stereotype ("girls exploiting men for drinks"), and the suggested response is to adopt deliberate hostility and disrespect as a strategy; it is generalizing an entire group and justifying contempt toward them. The "lesson" explicitly encourages treating interactions as transactional and frames social interaction primarily as a negotiation for sex. Whether or not some individuals behave opportunistically, promoting that mindset as a general rule is ethically questionable. Most importantly, the outcome does not validate the approach as healthy behaviour and even Feynman himself makes it clear at the end that the method was effective in a narrow sense but not enjoyable or aligned with how he ultimately wanted to interact with people. That distancing is important context: it suggests the episode was more an observation about social dynamics than a recommendation for how people should behave.
- willtemperley 9mo agoThank you I’ve been looking for this. His method of delivery is so clear I find it immensely relaxing.
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- thomasahle 9mo agoOn the topic of lecture notes, I can really recommend Scott Aaron's Quantum Information lecture notes: https://www.scottaaronson.com/qclec.pdf https://www.scottaaronson.com/qclec.pdf
- porknbeans00 9mo agoGod Feynman was such an amazing teacher of complex topics. Never miss upvoting this guy. His involvement in NASA and challenger investigations specifically are also legendary. Watch more Feynman. Totally worth the time investment.
- redditor98654 9mo agoMy introduction to Feynman was more from other science communicators either quoting him or retelling some story about him and initially it formed a mental picture in my mind that he might be one of those personalities more famous culturally than for his actual scientific achievements. Like how in sports often the more popular players may not be the actual “best” one purely from the sporting skills pov. But then I read more about him and yeah, he is indeed the real deal.
- latexr 9mo agoThis is fantastic. I recently regained an interest in revisiting Feynman lectures but several audios I found on YouTube left me uneasy that they could be AI-generated. I aimed to ensure good sources before diving in again, but hadn’t yet had the opportunity to do so. The videos are particularly interesting in how they include a transcript which is auto-highlighted and one can click around the text to move in the video. That’s a great mode of interaction I wish were more common. I have only found it in Apple’s WWDC videos. It’s missing a way to link directly to a timestamp, and when switching videos from the tabs the URL doesn’t change, but those are minor inconveniences considering the rest of the website. Also kudos on choice of using the structure of the atom image as the “loading” graphic. Thank you to the authors for putting this together.
- thetwentyone 9mo agoI’ve been looking for a way to listen to the audio offline, but this website is very resistant to scraping. I’d appreciate if anyone knew of a free or paid place to download the audio lectures.
- ajb 9mo agoAlong these lines, one of the early popular science works is "Letters to a German Princess", which compiles Euler's letters on Natural Philosophy (which is mostly what we today call science and maths) which he was commissioned to write as part of her education. Many were keen to educate their daughters as well as royalty, so the book version sold well. It is, of course, very out of date in terms of the science. https://en.wikipedia.org/wiki/Letters_to_a_German_Princess https://en.wikipedia.org/wiki/Letters_to_a_German_Princess
- rramadass 9mo agoDang! Just when i thought i had a fair idea of Euler's breadth of knowledge/contributions along comes this new (for me) find. Thanks for the pointer. PS: Obviously, it is nothing like nor comparable to Feynman Lectures which is modern science but an interesting piece of scientific history.
- assemblyman 9mo agoIt is very interesting to see completely different impressions of Feynman from comments here. As a physicist, I first got introduced to Feynman from his popular QED book as a freshman in college. Over the years, I came to admire his contributions and way of thinking but could also see the cult of personality that has formed. Feynman is definitely not like Neil deGrasse Tyson or Kaku. He was a very creative and technically sophisticated physicist. All his popular books are based on lectures he wrote and gave but they were mostly "side projects" e.g. computation, lectures on gravitation, six easy pieces etc. To get a better sense of his work, I would highly recommend: - The Beat of a Different Drum by Jagdish Mehra - Genius: The Life and Science of Richard Feynman by James Gleick - Selected Papers - https://www.worldscientific.com/worldscibooks/10.1142/4270 https://www.worldscientific.com/worldscibooks/10.1142/4270 (expensive and technical) - QED and the men who made it by Schweber There are also many historical physicists who are surprisingly unknown outside the field - Schwinger, Tomonaga, Landau, Sidney Coleman, Murray Gell-mann, Nambu, Steven Weinberg, Ken Wilson, Curtis Callan etc. I just randomly picked a few names before the 90s but these are all scientific giants. For example, Schwinger's papers are notoriously hard to read but his books are great after a first course. Sidney Coleman gave beautiful lectures on QFT. Landau is extremely famous for his 9 books with Lifshitz. It definitely is very surprising that Feynman has such an outsized share of interest. Maybe because he was a gregarious outgoing character? Another interesting aspect is how a person is often viewed as an authority or even a genius because their work introduces an audience to the subject. Feynman with his lectures. To a far lesser extent (in my opinion), one sees this with Andrej Karpathy and Jeremy Howard. This is not to take away from their wonderful teaching work. I know how hard it is to distill material and convey it. But, there's a whole web of contributions that leads to a subject maturing enough to be taught clearly. As I get older, I find it less useful to assign labels (names) to discoveries and contributions. As Feynman himself said in a lecture after drawing a Feynman diagram, "this is THE diagram" (and not the Feynman diagram).
- ThrowawayR2 9mo agoFeynman had the vanishingly rare combination of being at world-shaking (literally) historical events like the Manhattan Project and the Trinity test that ordinary people can relate to¹, actual scientific contribution enough to merit a Nobel Prize in Physics, and being an engaging storyteller and educator. I don't think it's all that surprising that his recognizability very high. ¹ Ordinary people can relate to a giant industrial project and a huge boom. They cannot relate to some person sitting in a room writing arcane symbols and muttering to themselves until one day they yell "Heureka! Ich hab es gefunden!" or whatever the proper German is and rush off to publish a paper.
- theendisney 9mo agoTo a suspicious extend the internet is full of articles praising the man. With the exception of the stripclub story (which only barely makes the cut) it is as if nothing negative was ever written about him. The www echochamber just doesnt want to hear it. People get even more mad if you tell them there are many reasons to think Joseph Papp created a mixture of noble gasses, injected into sealed pistons of conventional combustion engines and then those engines would run for 6 months without adding any other fuel. Feynman was amoung the angry mob. After hearing about it he went to a demonstration involving a big volvo engine funded by the navy. After 10 min he climbed onto stage pointed at some electronics plugged into the wall, he pulled the plug and playfully dangled it above papp who protested loudly and said it was not safe. Feynman ignored him until papp went into full panic. The plug was returned, papp put it back into the wall and the engine exploded. 7 people were injured, one lost a leg and one audience member died. The dubious thing to me was that after much media exposure no one was interested in the physics. Feynman oddly twists the story and said papp unplugged it and gave the plug to him. He wanted to hold it he said. He also created a fantastic imaginary forensic report where he imagined papp put explosives in the engine. After papp blamed him for destroying the engine they settled out of court. The noble gas engine was now officially debunked. https://hoaxes.org/comments/papparticle2.html https://hoaxes.org/comments/papparticle2.html It gets more absurd where journalists and internet septics make an effort to change the story. https://skeptics.stackexchange.com/questions/28530/did-richard-feynman-see-josef-papps-machine-explode https://skeptics.stackexchange.com/questions/28530/did-richa... I generously give the Papp engine 0.1% odds of being useful technology which means we should be looking at the thousand claims of miraculous tech. If i look at the debunking there is never any evidence against them. Look at them fabricating, its quite amusing. Or do you see a single convincing argument the engine doesnt work even from the highly praised Feynman himself?
- DoctorOetker 9mo agonone of this matters, the probability of new physics here is essentially nil. if anyone is irresponsible its Papp who knowingly handed the plug to a productive skeptic, knowing full well the dangers of the device. if the motor had any merit, he could refuse the out-of-court settlement and demonstrate the working principles of his motor, but he didn't! he took the money, Feymann inadvertently saved him from certain humiliation had this not occured. hiding rocket propellant in a perpetuum mobile must be one of the most dangerously retarded things to do, people will come closer and inspect and try to figure out the true power source, and they will home in on your panic reactions to get closer (warmer - colder style).