Ask HN: How to self-study physics? • Hacker News Board

Re: Ask HN: How to self-study physics?

#121

Post by jshevek » Thu, Mar 26, 2020, 5:12 PM UTC

andrepd wrote: post #100

ukj wrote: post #88

Earlier quoted context omitted.

I am to really glad to hear commentary like this coming from physicists. (read: glad to see others siding with my biases). Ceteris paribus there is one significant distinction between Mathematics and Computer Science: state. The Mathematical Universe is immutable/stateless/timeless. The Computational Universe is mutable/stateful/time-bound. The observer effect in physics can be trivially expressed and evaluated as a…

>The observer effect in physics can be trivially expressed and evaluated as a mutating getter in any programming language. >It cannot be expressed in any Mathematical grammar. What on earth are you trying to say...? There is a whole mathematical treatment of quantum mechanics, measurement effect included (several treatments). More to the point, any algorithm can be formalised in e.g. a Turing machine, or any other eq…

>This reeks of Dunning-Kruger: you don't even know enough about what you're talking about to realise how badly little sense you're making. I strongly suggest you familiarise yourself with a topic before opining about it. I'll be hard-pressed to believe you ever opened a physics textbook in your life after high school. Why then do you feel the need to talk blindly about it?

You can just address their ideas, this extra stuff isn't helpful.

Re: Ask HN: How to self-study physics?

#122

Post by Koshkin » Thu, Mar 26, 2020, 5:12 PM UTC

codebolt wrote: post #11

I highly recommend Road to Reality by Roger Penrose. Takes you all the way from classical through modern physics, and introduces all the necessary math. Gives you a good overview of the territory, but you might want to supplement with some extra literature/lectures to go more in-depth certain places.

Penrose's is a terrible book for a beginner to try to learn from. It's a weird mix of relatively simple stuff and one you can't possibly appreciate if you do not have a degree in math or physics. It has a tendency to dwell on simple and familiar things and then rush through rather involved topics that are no doubt something a beginner would not have a chance to be prepared for.

Re: Ask HN: How to self-study physics?

#123

Post by madhadron » Thu, Mar 26, 2020, 5:13 PM UTC

Simon_says wrote: post #69

impendia wrote: post #68

Hi hsikka, Are you a PhD student? And if so, are you aiming at a career in academic research? I'll offer my advice as a math professor, and as someone who supervises students. If you want to get a strong foundation in physics, then reading Halliday + Resnick, and doing a large number of the exercises, would be one good way to go about it. (Look for used copies of previous editions on Amazon -- they'll be cheap.) Ther…

How does Halliday + Resnick compare to Young + Freedman?

I personally really like the old (1960's) editions of Halliday and Resnick. I feel they are superior to the editions published today, and are available for very cheap.

Re: Ask HN: How to self-study physics?

#124

Post by pks016 » Thu, Mar 26, 2020, 5:13 PM UTC

impendia wrote: post #68

Hi hsikka, Are you a PhD student? And if so, are you aiming at a career in academic research? I'll offer my advice as a math professor, and as someone who supervises students. If you want to get a strong foundation in physics, then reading Halliday + Resnick, and doing a large number of the exercises, would be one good way to go about it. (Look for used copies of previous editions on Amazon -- they'll be cheap.) Ther…

+1 for Resnick Halliday or Fowler. Don't start with Freyman. I made that mistake, wasted a lot of time.

Re: Ask HN: How to self-study physics?

#125

Post by blablabla123 » Thu, Mar 26, 2020, 5:14 PM UTC

Probably first you should get a rough idea what you want to learn. When I studied Physics the standard track was Mathematics, Experimental Physics (Mechanics, Electrodynamics), Theoretical Physics (Mechanics), and then other topics, Wave Physics, Thermodynamics, Solid state Physics and Particle Physics. Normally first the experimental course comes and then usually with some delay the theoretical.

Still, you can decide if you want more Mathematics, more Theory or less. (Probably the CS Maths should get you covered pretty well for the start) I'd do a research on popular recommendations of books and then see which ones you like and interest - the styles and contents are often so different. While going through the books you can try to find nice YouTube videos and other stuff.

Of course you get a deeper understanding when doing some exercises, although this can be tough. I'd highly recommend finding a book that has a solution section/solution book or maybe some online course that offers that. The exercises for Experimental Physics are usually not long but can be surprising. ;) Also it might be surprising that depending on your interest a strong foundation in Mathematics is not critical, although you'll still need to wrap your head around the common math problems.

One motivating thing is that while you go through the topics (Mechanics, Electrodynamics, Wave theory, QM, ...) the frameworks and approaches are somewhat repetitive and just get more sophisticated over time.

TL;DR: pick a curriculum and combine it with your favorite material

Re: Ask HN: How to self-study physics?

#126

Post by propter_hoc » Thu, Mar 26, 2020, 5:20 PM UTC

scottlocklin wrote: post #74

For the love of God, don't use Feynman lectures to learn physics. That's something you read after you know physics, for relaxation and conceptual stuff. Resnick & Halliday is a much better freshman/sophomore book. Susskind's "theoretical minimum" is actually pretty good. http://theoreticalminimum.com/courses Fowler gives a pretty conventional undergraduate physics curriculum (adding Feynman in there somehow). If it w…

I can't believe I am reading a recommendation that someone with little background in E&M self-studies with Jackson. That book is incredibly difficult even with a great graduate-level professor.

Re: Ask HN: How to self-study physics?

#127

Post by Hasz » Thu, Mar 26, 2020, 5:25 PM UTC

I would like to add one of my favorite mathematical "cookbooks" -- "Mathematical Methods in the Physical Sciences" by Mary Boas.

Bad Integrals? Tensor Analysis? Fancy functions and special polynomials? PDE tricks?

Boas has solutions!

Methods are practically explained and succinct. It's my favorite book to brush up on a old technique or learn some new methods.

Wolfram's Mathworld is also a good reference, but not as much of a learning tool.

Re: Ask HN: How to self-study physics?

#128

Post by AnthonBerg » Thu, Mar 26, 2020, 5:25 PM UTC

ska wrote: post #114

AnthonBerg wrote: post #111

Earlier quoted context omitted.

We all learn differently. Please don't deal in pedagogical certainties that may close doors unventured. Feynman's lectures were crucially eye-opening for me and many others.

It's pretty well established now that Feynman is not a good general approach for introductory physics. Plenty of talented teachers have tried it, and moved on to something more effective. This doesn't contradict your point. A particular individual may find them very helpful in learning and understanding the foundational stuff. By all means try, and if it works for you, great. However, it shouldn't be at the top of an…

Exactly. I ask that the applicability of Feynman’s lectures is not presented in absolutes - not always, not for everyone, not never.

But definitely sometimes for some. Including to start with.

They’re quite beautiful.

Re: Ask HN: How to self-study physics?

#129

Post by throwqwerty » Thu, Mar 26, 2020, 5:26 PM UTC

propter_hoc wrote: post #126

scottlocklin wrote: post #74

For the love of God, don't use Feynman lectures to learn physics. That's something you read after you know physics, for relaxation and conceptual stuff. Resnick & Halliday is a much better freshman/sophomore book. Susskind's "theoretical minimum" is actually pretty good. http://theoreticalminimum.com/courses Fowler gives a pretty conventional undergraduate physics curriculum (adding Feynman in there somehow). If it w…

I can't believe I am reading a recommendation that someone with little background in E&M self-studies with Jackson. That book is incredibly difficult even with a great graduate-level professor.

academic virtue signaling. like people recommending TAOCP to people that don't know how to program or rudin (either one!) to people that don't know any math.

Re: Ask HN: How to self-study physics?

#130

Post by madhadron » Thu, Mar 26, 2020, 5:27 PM UTC

It would help to know what background you have and what interests you/what you hope to get out of it. Did you have basic physics in undergrad?

Foundation can mean a lot of things. It can mean having a really solid grasp of how Newtonian mechanics is put together. It can mean having a solid grasp of doing experimental physics on classical systems. It can mean having a mathematical understanding of symplectic manifolds and quantization. It can mean replacing your naive physical model of motion in your hind brain with a learned, Newtonian model.

If you've never done any lab work, actually getting a stopwatch and conducting experiments with balls rolling down inclined planes and the like can be...eye opening.

You will need problems to work, otherwise anything you do is superficial. For example, here's a collection of elementary physics problems: https://archive.org/details/BukhovtsevEtAlProblemsInElementa... (The Russians were great about building this kind of collection.)

If you can give some more detail, it will help us direct you better.