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The Feynman Lectures on Physics (1961-1964)

feynmanlectures.caltech.edu

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Re: The Feynman Lectures on Physics (1961-1964)

#31

Post by Isamu »

colmmacc wrote: post #3

Lesser known but possibly more relevant to most HN readers are Feynman's lectures on computation - 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.

Apropos of Feynman on computing, the story of his time working at Thinking Machines Corp 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.”

Re: The Feynman Lectures on Physics (1961-1964)

#32

Post by emmelaich »

traes wrote: post #21
DiogenesKynikos wrote: post #16

Earlier quoted context omitted.

The guy invented the path integral in his PhD thesis. He invented Feynman diagrams and figured out how to do finite calculations in quantum electrodynamics. Unless you're a perfect human being, please, cut him just a tiny bit of slack.

I understand not watching a 3 hour video before leaving a comment, but this is a disrespectful reaction to a very well thought out video by a professional physicist giving a nuanced opinion about Feynman's legacy. She acknowledges many times in the video that Feynman was a great physicist who deserved his Nobel prize. The central topic of the video is dissecting his public image and the many books published under his…

He was accused, in divorce papers. And it wasn't beating, FWIW.

Re: The Feynman Lectures on Physics (1961-1964)

#33

Post by CamperBob2 »

Ardren wrote: post #17
chadrs wrote: post #13

"the sham legacy of Richard Feynman" https://www.youtube.com/watch?v=TwKpj2ISQAc

Brave to link to that here.

It just wears thin after a while. Nobody studies Feynman to learn social skills or sexual ethics. If they did, these types of complaints would certainly be relevant... but they don't, and they aren't.

Re: The Feynman Lectures on Physics (1961-1964)

#34

Post by dgfl »

jesuslop wrote: post #23
colmmacc wrote: post #3

Lesser known but possibly more relevant to most HN readers are Feynman's lectures on computation - 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.

Interesting, 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 whe…

Feynman 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-... 2. https://www.zyvex.com/nanotech/feynman.html

Re: The Feynman Lectures on Physics (1961-1964)

#35

Post by melling »

CamperBob2 wrote: post #33
Ardren wrote: post #17

Earlier quoted context omitted.

Brave to link to that here.

It just wears thin after a while. Nobody studies Feynman to learn social skills or sexual ethics. If they did, these types of complaints would certainly be relevant... but they don't, and they aren't.

People also don’t think he’s one of the greatest physicists ever.

As he said, he was just an ordinary person who worked very hard.

Re: The Feynman Lectures on Physics (1961-1964)

#36

Post by emmelaich »

opello wrote: post #30
chadcmulligan wrote: post #25

Earlier quoted context omitted.

misogynistic behaviors were cultural at the time, I agree they're abhorrent but people are embedded in their culture. The same is said of Hitchcock, (as an example) and his behaviour was unacceptable by todays standards. We've come some way from that but still a way to go. From the about the authors in the OP's link "Feynman was a remarkably effective educator. Of all his numerous awards, he was especially proud of t…

> misogynistic behaviors were cultural at the time, I agree they're abhorrent but people are embedded in their culture. The same is said of Hitchcock, (as an example) and his behaviour was unacceptable by todays standards. We've come some way from that but still a way to go. The video actually addresses this very point in the first few minutes: > the second component of the Feynman lifestyle that the Feynman bro has…

I do not think Feynman was celebrating his activity in the book. From memory, he learnt the behaviour from other bar flies at the bars he hung out. And he expressed his surprise at how some women reacted. This was far from his upbringing and his experience with his fiancee.

The behaviour is hardly laudable, but "celebrated" it is not.

Re: The Feynman Lectures on Physics (1961-1964)

#40

Post by kmaitreys »

mananaysiempre wrote: post #22
delichon wrote: post #11

Poets 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 belc…

A 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 en…

I 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).

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