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So you want to learn physics (2021)

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Re: So you want to learn physics (2021)

#121

Post by kxyvr »

meristem wrote: post #81
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

Do you have text/other sources suggestions for this? I agree with you, would like to learn more.

For the mathematically inclined, the best I've seen is An Introduction to Continuum Mechanics by Morton Gurtin from 1981. At one point, it could be purchased from Google books directly as a pdf.

Re: So you want to learn physics (2021)

#122

Post by commonlisp94 »

consilient wrote: post #120
simonh wrote: post #99

Earlier quoted context omitted.

Idiot who transferred from physics to computer science after year 1 here, so please make allowances. But all of those phenomena are emergent. Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena? Obviously there needs to be a transition, but at some point you go from physics to engineering. I suppose it depends what specialty in physics you go into. Nobody c…

> Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena? Obviously there needs to be a transition, but at some point you go from physics to engineering. 1. The boundaries between disciplines are where they are in part by historical accident, and in part because that's what the people working in them find useful - there is no actual fact of the matter. 2. We d…

> there is no actual fact of the matter.

This is true of all categories, so not a helpful comment. I suspect someone has a good enough definition.

Re: So you want to learn physics (2021)

#123

Post by bkcooper »

amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

You might be interested in Kip Thorne (of Gravitation fame) and Roger Blandford's book Modern Classical Physics, which is designed to cover the elements of non-quantum physics that are generally ignored in the first year PhD curriculum. Part headers: statistical physics; optics; elasticity; fluid dynamics; plasma physics; general relativity

Re: So you want to learn physics (2021)

#124

Post by whartung »

brightlancer wrote: post #66
javajosh wrote: post #24

Earlier quoted context omitted.

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…

> What I'd like to see more of in physics texts is presenting a problem before offering the solution. Yes. > If you present the hard problem first, the student may flail around and realize: I need something to help with this! Now that they know they need it, and why, you can give them the tool that fits the bill. No. If an instructor deliberately gives a student a problem that they know the student _cannot_ solve, th…

  > As a practical matter, many of my college classes went too quickly to do anything _but_ teach the solution
My calculus instructor in college was one of those where they'd go through the problem and on step 7 (or whatever) go "Oh, where did we make the error?" where we'd all flail until they pointed us back to step 3 and then had to redo everything all over again. It was, for me, the most maddening way to teach. I was struggling just to get everything copied from the board to experience it by rote, completely unprepared to even process what was going on, much less have to go back and redo everything all over again.

I dropped that class. I always felt it was a mistake not taking calculus in High School. I had a very good relationship with the math teacher there, and we could have done it, to some level, casually between classes. I just didn't take him up on it.

I've never learned calculus.

Re: So you want to learn physics (2021)

#125

Post by radioactivist »

bkcooper wrote: post #123
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

You might be interested in Kip Thorne (of Gravitation fame) and Roger Blandford's book Modern Classical Physics , which is designed to cover the elements of non-quantum physics that are generally ignored in the first year PhD curriculum. Part headers: statistical physics; optics; elasticity; fluid dynamics; plasma physics; general relativity

I second the recommendation of this book -- it really is quite excellent and covers at an advanced level most of what is commonly left out of a modern physics curriculum (though it is quite imposing in its size/weight).

Re: So you want to learn physics (2021)

#126

Post by paulpauper »

It seems like we're in a sort of 'autodidacticism boom'. I see this so much in almost everything now--physics, math, MIT courses online, etc. I think this is symptomatic of how people have lost faith in institutions--be it colleges, schools, govt, etc.--and see the DIY route as being better, or maybe schools are doing a poor job teaching or costs are too high, such as tuition. But why the sudden, huge interest in DIY math and physics especially? I dunno.

Re: So you want to learn physics (2021)

#127

Post by coliveira »

ecshafer wrote: post #61
ChuckMcM wrote: post #35

Earlier quoted context omitted.

Totally 100% with this. When younger I thought I could read the material and say "Oh, okay that makes sense I understand this." Only to fail miserably when on a test or somewhere I had to apply what I "knew" and realizing I didn't actually know it. I lean strongly toward autodidacticism and learned that if I could solve problems with the technique then I knew it.

My calculus 1 professor gave the advice that the best way to study is to do every problem in the book, then go and get another book and do every problem in that book, and keep doing that until you look at a problem and know exactly every step to do immediately.

That's how I learned probability theory. I studied from one book and solved all problems, then moved to the next, until it became second nature. Probability theory is one of the topics that you will never learn by only reading, it is necessary to develop the necessary intuition.

Re: So you want to learn physics (2021)

#128

Post by titanomachy »

LYK-love wrote: post #78

After reading this blog, I'm ashamed. I just graduated from college. In my high school, the education of physics was so boring and tiresome that I even hated it at one point. For this reason, I chose computer science rather than physics as my major in college. Later, I gradually became interested in physics, however, due to the lack of good enough study habits, atmosphere and courage (which is a self-deprecating way…

Go easy on yourself.

Re: So you want to learn physics (2021)

#129

Post by radioactivist »

ayakang31415 wrote: post #118
amluto wrote: post #65

This has the same omission that my undergrad program had: continuum mechanics. Even just the very basics (pressure, velocity, etc in a moving, non-equilibrium system) and translating between the terminology used by different science and engineering fields (static pressure, total pressure, velocity pressure, stagnation pressure, hydrostatic pressure, dynamic pressure, plain old pressure, head, oh my!) is very useful.…

The undergraduate Physics program is, in my opinion, heavily influenced by the working physicists in the field. Lots of physicist who work in fundamental physics is either particle physicists or work with models that are in particles. Those are the ones who teach physics in undergrad.

This is simply not true, condensed matter physics makes up the largest sub-field of physics (about half by some estimates).

I think the more relevant aspect is that to reach the frontier in a wide array of fields you a solid grounding quantum physics (and several other "new" -- i.e. within the last century or so -- topics) that have displaced more "old-fashioned" topics like continuum mechanics.

Re: So you want to learn physics (2021)

#130

Post by SamBam »

civilitty wrote: post #39
belugacat wrote: post #22

Earlier quoted context omitted.

That’s a POV I’ve grown to adopt as I got older (like many, perhaps). I used to heavily privilege theory, believing that everything could (and maybe should) be derived from first principles. Now I place the concrete over everything else; theory is nice when it can illuminate why the practice works. Otherwise, it’s just words. The most frustrating is when I have friends who have derived their entire understanding of a…

> That’s a POV I’ve grown to adopt as I got older (like many, perhaps). I used to heavily privilege theory, believing that everything could (and maybe should) be derived from first principles. > Now I place the concrete over everything else; theory is nice when it can illuminate why the practice works. Otherwise, it’s just words. That mirrors the trajectory of all humankind, doesn’t it? From lofty Platonic ideals to…

An odd hypothesis, I think. I don't think our ancestors were any less practical than us. Probably a great deal more practical, in fact.

You reference Plato, but you could easily phrase it in the other direction. "From Roman engineering to Wittgenstein blithering on about meaning."

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