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So you want to learn physics (2021)

susanrigetti.com

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Re: So you want to learn physics (2021)

#41

Post by jore »

bluish29 wrote: post #37

> Classical Electrodynamics by Jackson (essential). This is the bible of classical electrodynamics, and everyone who works through either loves it or hates it (I loved it). I agree that there is a division between who loves that book (like the author) and the majority of the graduate students who had nightmares (and sometimes still gets). I like this goodreads review of the book [1] > A soul crushing technical manual…

It is interesting that 2 years later the same reviewer changes their mind a bit:

> Now, a few years after writing that review, I must return to say that as much as I hate this book, it's probably the best textbook that I have. I constantly return to it to reteach myself basic concepts or math. The problem with the text is that in order for it to be useful, you pretty much have to already understand the material. It's a dense, technical manual that, when paired with an easier to understand text such as Griffiths, grants tremendous power. Don't get me wrong, if there is a hell, I personally hope John David Jackson is burning in it right now, but I also have to tip my hat to him

Re: So you want to learn physics (2021)

#42

Post by whartung »

javajosh wrote: post #24
qsort wrote: post #3

A point that's rightfully emphasized by the author: > Solving problems is the only way to understand physics. There's no way around it. This generalizes well to other fields. I don't want to discourage anybody from trying to educate themselves in a difficult field (be it physics or something else), but that's a very common and immediately visible problem with autodidacts. If you haven't worked through enough hard pro…

Yes, and I'd take it further. What I'd like to see more of in physics texts is presenting a problem before offering the solution. Too often you get what amounts to a laundry list of techniques and ideas, which are the components to the answers to hard problems, but the student isn't motivated to learn them. If you present the hard problem first, the student may flail around and realize: I need something to help with…

  > If you present the hard problem first, the student may flail around and realize: I need something to help with this!
I suffer from this. Sure, I'd like to learn physics, but what I don't want to do is learn all of it. Right now. Because what I'd rather learn is what I need to solve the problem I have. It's a silly problem, it's not real world, but it's my problem that I'd like solved.

As I've grabbed my horse and lance and rushed at this windmill from assorted directions, I quickly run into my limitations that prevent the problem being solved. I run into vocabulary problems with the math, the fact that I simply don't have the math to approach the problem (which appears to be some vector calculus -- I think. "No, you idiot, it's XYZ instead", but I don't know enough to know that it's not vector calculus, if, indeed, it isn't). I try to apply basic kinematics to the problem, but I don't know if that's enough. And, finally, it could be all of those things plus, oh, some optimization issues and, also, would you like to be introduced to the several different techniques for computing numeric integration and the differential equation solvers?

"Eeep!"

To quote the film "Addams Family Values":

  Wednesday: Pugsley, the baby weighs 10 pounds, the cannonball weighs 20 pounds. Which will hit the stone walkway first?
  Pugsley: I'm still on fractions.
So, yea, that's me, I'm Pugsley. It seems I need 2+ years of mechanics, calculus, and differential equations, and, probably, some time with computer based simulation all to chart the course for a spaceship to a planet for a 40 year old role playing game. Of course, I don't know what the, perhaps, abbreviated path I could take through those domains to get to be able to answer my question. That might knock a year off the study, but, unlikely. "Better to have all of the foundation" and all that. Which is true, but I'm kind of after the "reward" part here, not so much the "journey".

Re: So you want to learn physics (2021)

#43

Post by elashri »

libraryofbabel wrote: post #38
bluish29 wrote: post #37

> Classical Electrodynamics by Jackson (essential). This is the bible of classical electrodynamics, and everyone who works through either loves it or hates it (I loved it). I agree that there is a division between who loves that book (like the author) and the majority of the graduate students who had nightmares (and sometimes still gets). I like this goodreads review of the book [1] > A soul crushing technical manual…

Well yes, but curious what book you would recommend instead for graduate electrodynamics? Note that she already recommends first studying Griffith's Introduction to Electrodynamics at the undergraduate level (and that one is a true pleasure to read imho).

I'm happy that many professors start to use Zangwill's Modern Electrodynamics [1] textbook. It seems more focused on explaining things and don't assume that you know too much (which you usually have no idea if you should have known something or you just an idiot) like Jackson.

[1] https://www.amazon.com/dp/0521896975/

Re: So you want to learn physics (2021)

#45

Post by ajkjk »

abhayhegde wrote: post #7

This guide does contain the books that are usually recommended in a university course setting! So, it will require significant amount of time and effort to master it. One of the series of books that physicists religiously stick to is Landau and Lifschitz. But my experience has been that it's worth it only if you already have some basic understanding.

Landau and Lifschitz are terrible books, pedagogically speaking. They're good only in that they're exhaustive and rigorous.

Re: So you want to learn physics (2021)

#46

Post by remote_phone »

qsort wrote: post #3

A point that's rightfully emphasized by the author: > Solving problems is the only way to understand physics. There's no way around it. This generalizes well to other fields. I don't want to discourage anybody from trying to educate themselves in a difficult field (be it physics or something else), but that's a very common and immediately visible problem with autodidacts. If you haven't worked through enough hard pro…

In college, I was always the first one out of my friends to “get” a concept, like fast Fourier transforms, anything with signal processing or even coding or any labs we had to do etc so I would spend time teaching them in the library. However I never did any of the exercises, mostly due to laziness and not arrogance. They would get A’s and I would get C’s and D’s.

I emphasize this story to my kids because knowing isn’t important because everyone eventually figure it out. It’s the ones who can do the problems and get good marks that succeed in the end.

Re: So you want to learn physics (2021)

#47

Post by superposeur »

kingkongjaffa wrote: post #13

It’s a decent list but thermodynamics is introduced way too late in the list (after modern and quantum wtf) and fluid dynamics and fluid mechanics including aerodynamics is entirely missing. If you have a physics education (I have an engineering education) can you tell me if you can really get a physics degree without bumping into Bernoulli or Navier-Stokes? At least just to see the lay of the land.

As a physicist, fluid mechanics was the most glaring gap in my undergraduate preparation, despite its centrality to most physics applications. Somehow it is always a “time permitting” topic at the end of an already-cramped curriculum.

I first encountered the Euler equation in the context of GR — absurd. In another decade or two, I suspect its rightful place early in the physics curriculum will be emphasized.

Re: So you want to learn physics (2021)

#48

Post by srameshc »

I love HN for thing like these that I wouldn't have otherwise found out. I used to think often about physics but not seriously enough to search for resources on how to get started and learn. But now that I have this guide (thank you Susan), I think I will start and no longer wonder or plan for learning physics in the future.

Re: So you want to learn physics (2021)

#50

Post by tayo42 »

> they are and have been dreadfully underserved and underestimated by the academic physics community (who do not take them seriously because they aren’t studying at colleges and universities)

This stuck out, pretty rigorous if all you want to satisfy your curiosity. If you want to actually apply any of the hard work you put in, you need a degree.

I think that is the most interesting part of learning anything, applying it interesting ways. Doing that within so many of the areas of study is still gated behind academics.

That killed my motivation for putting effort into most things, pretty much except computer science where we are still ok with trusting self taught people for some reason. But to do anything interesting physics, astronomy, philosophy too you need to be in school. sucks

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