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Probability (1963)

by rcshubhadeep on 10/10/22, 8:46 AM with 185 comments

  • by hackandthink on 10/10/22, 11:36 AM

  • by wodenokoto on 10/10/22, 12:34 PM

    If you scroll to the top there's a camera icon. If you click, you can view photos from the actual lecture

  • by sillysaurusx on 10/10/22, 9:33 AM

    It’s worth noting (much to my surprise) that the Feynman lectures on physics weren’t written entirely by Feynman. I’ve often wondered whether the wonderful conversational style I’ve associated with him is actually him, or one of his contemporaries.

    Either way, this is a great chapter on probability. Thanks to whoever wrote it!

  • by deltasevennine on 10/10/22, 10:09 AM

    I have a related question to this topic. Is probability axiomatic to reality? Does it exist on the same level as logic where logic is axiomatic to reality and just assumed to be true? Or is it simply a phenomenon arising from logic?

    It seems like probability just happens to work without explanation? Intuitively this seems a bit strange since it feels as though probability should be derived from something else. Not sure if I'm correct here.

    What confuses me even more is that I do know logic can be defined in terms of probability. Causal connections can be probabilistic. If A then 25% chance of B and so on.

  • by graycat on 10/10/22, 11:31 AM

    Sorry, Feynman, whatever else he did, on probability he gets a grade of flat F. Here is why: In his book Lectures on Physics he states that a particle of unknown location has a probability density uniform over all of space. No it doesn't. No such density can exist. Done. Grade flat F.

    I tried to be a physics major but could not swallow all the daily really stupid mistakes such as this one by Feynman I got each physics lecture and I didn't have time both to learn the physics AND to clean up the sloppy math. So, I majored in math.

    As I learned the math, from some of the best sources, I came to understand just how just plain awful the math of the physics community is.

    Then in one of the Adams lectures on quantum mechanics at MIT I saw some of the reason: The physics community takes pride in doing junk math. They get by with it because they won't take the math seriously anyway, that is, they insist on experimental evidence. So, to them, the math can be just a heuristic, a hint for some guessing.

    Students need to be told this, in clear terms, early on.

    It went on this way: In one of the lectures from MIT a statement was that the wave functions were differentiable and also continuous. Of COURSE they are continuous -- every differentiable function is continuous.

    The lectures made a total mess out of correlation and independence. It looks like Adams does not understand the two or their difference clearly.

    There was more really sloppy stuff around Fourier theory. I got my Fourier theory from three of W. Rudin's books. It looks like at MIT they get Fourier theory from a comic book.

    I got sick, really sick, of the math in physics. Feynman on probability is just one example.

  • by sylware on 10/10/22, 10:01 AM

    What's astonishing: many laws of physics emerge from statistical approximations of quantum mechanics.

    One day, if I really get into quantum mechanics, I will try to understand how they rebuilt maxwell equations from QED.

  • by BOOSTERHIDROGEN on 10/10/22, 10:14 AM

    Any statistics book that have similar approach like this ?