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So You Want to Learn Physics (2016)

susanjfowler.com

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Re: So You Want to Learn Physics (2016)

#41
post #5

> ...the pure joy of understanding the universe around us is one of the most beautiful experiences you can ever have in life. But you do not need to study physics for 25 years in order to understand how the world works. Academic physics that she wants us to learn to undersdand the world is just a new academic subject invented or formalized in the 19. century. Archimedes knew 0 (zero) physics and made huge discoveries…

A lot of times you don't know what you need. The point of a good curriculum is to help you avoid those situations as much as possible.

If the goal is to try to understand nature, make your own curriculum. Most people, myself included, initially believe the physics hype and believe that by studying academic physics they will gain new understanding of nature. I believe this is not the right way. It is better to start by asking a specific question. For instance, I am curious about what matter is. So I ask myself What is matter? and try to answer this question. I divide my question into smaller questions. Until I find a question easy enough to answer. I take it from there. But if I enter a physics curriculum in a university, I won't be able to ask this question for 20 years. The answer will always be in the future.

Re: So You Want to Learn Physics (2016)

#44
post #23

Well I disagree with many of the book choices, but if there's one thing that's absolutely spot-on is this: >One big problem is that a lot of the popular books written about physics (especially those by famous physicists) are incredibly speculative and tend to present an unrealistic view of what the study of physics is all about. When you're learning physics, it's good to avoid these types of speculative books, and st…

I have a model with two kinds of knowledge: sexy knowledge and homely knowledge. I think the internet and mass media era in general have massively endorsed and empowered the projects and acquisition of sexy knowledge. If it doesn't garner attention rapidly on a large scale, then it doesn't go on TV. The problem is that most of the real projects of science and industry are about homely knowledge. It's the little boring things like washing your hands that prevent catastrophic hospital deaths. But that's not superficially interesting, or fun, and it doesn't provide the knowledge bearer with any kind of moral or intellectual superiority by which they can affect pretensions of enlightenment. Quackery has always been a thing, but I think sexy knowledge lies somewhere before the frontier of quackery. It's true, or plausibly true, information, but it is dramatically overvalued in our time and culture.

Re: So You Want to Learn Physics (2016)

#45
Wow what an amazing list. It will still take many years to learn all this material, but I think that a dedicated student could follow it and physics up big time! My time estimate for someone with normal intelligence level (i.e. not genius), starting fro scratch and learning part-time, would be 2-3 years. It's totally worth it though for the analytical power that learning physics gives the learner.

Some notes/links below:

> Before you begin studying physics and working through the topics in the sections below, you have to be familiar with some basic mathematics.

That is very true and often a big obstacle for people who have been out of school for some time. Note it's not enough to just be familiar with the concepts—you must achieve fluency with the procedures so you can use them as building blocks for later studies. For example, it's not enough to just read about the quadratic formula (-b ± sqrt(b^2-4ac))/(2a) and use it a few times, spending 5 minutes each time to think about the steps, plugging in the vars, etc.

Because solving quadratic equations is used so much in math and physics, you have to package that procedure as a reusable routine that you don't think about anymore and you can apply almost without thinking, in under 30 seconds. This "fluency with the basics" will ensure you're not slowed down when you reach the more advanced topics where solving quadratic equations is used.... and there is only one way to build fluency...

> Regardless of your learning style, you'll still need to solve the physics problems in each textbook. Solving problems is the only way to really understand how the laws of physics work. There's no way around it.

This. A thousand times this. I wish someone told me that when I was studying. It may not be fun to get stuck, go down the wrong path, doubt your abilities and feel stupid along the way, but that's what growth looks like. If every time you read a solution to a problem provided by someone else you gain one "knowledge unit," then finding the solution on your own is > 10 knowledge units. Forget 10x engineer, be a 10x learner—solve some problems!

> 1. Introduction to Mechanics [...] the basics of motion in a straight line, motion in two dimensions, motion in three dimensions, Newton's Laws, work, kinetic energy, potential energy, the conservation of energy, momentum, collisions, rotation and rotational motion, gravitation, and periodic motion. > You'll need to learn calculus while working through University Physics. >

Shameless plug, I wrote a book called No Bullshit Guide to Math and Physics that covers these exact topics. It would be a great starting point for someone who wants to review high school math and learn mechanics and calculus in an integrated manner. Here are some links if anyone wants to check it out:

- preview: https://minireference.com/static/excerpts/noBSguide_v5_previ...

- https://minireference.com/static/tutorials/conceptmap.pdf

- condensed printable tutorial: https://minireference.com/static/tutorials/mech_in_7_pages.p...

- reviews: https://www.amazon.com/dp/0992001005/noBSmathphys

Re: So You Want to Learn Physics (2016)

#46
post #23

Well I disagree with many of the book choices, but if there's one thing that's absolutely spot-on is this: >One big problem is that a lot of the popular books written about physics (especially those by famous physicists) are incredibly speculative and tend to present an unrealistic view of what the study of physics is all about. When you're learning physics, it's good to avoid these types of speculative books, and st…

I think this is still fair.

I mean when you study Physics you learn to use apparently confusing tools - theoretical or experimental - with confidence. Sometimes in areas that only few people find interesting/appealing, like for instance complex problems in classical mechanics or thermodynamics. Only 1% of the studies is about crazy, absolutely counter-intuitive stuff that sounds like Sci-Fi. But isn't that what differentiates the amateur from the Pro? ;)

I mean if people want to do actual Research Physics, they must either go to a University (offline or online) or be mega disciplined. In the latter case they need a few more books though/adjust them also to personal taste.

Re: So You Want to Learn Physics (2016)

#47
>Regardless of your learning style, you'll still need to solve the physics problems in each textbook. Solving problems is the only way to really understand how the laws of physics work. There's no way around it. Even though it can feel tedious at times, there's nothing more rewarding than figuring out a really difficult physics problem and realizing that you figured it all out yourself!

This is the only way. It's I how I moved from an EE undergrad to a theoretical physics PhD. As I come back to material it's a lesson I need to painfully relearn. (Something I re-re-re-learned in 2015 http://nbodyphysics.com/blog/2015/02/28/learn-physics-with-t...)

Re: So You Want to Learn Physics (2016)

#48

Books are too low bandwidth. You will get stuck, mostly on trivial stuff. Then what do you do? My advice is to find a teacher. If they are any good they will speed up the process by one or two (or more) orders of magnitude. Even the professionals do this.

Not everyone can afford thousands of dollars for tutoring. But forums and MOOCs are good.

Do you have any physics forums to recommend off the top of your head?

There are often interesting discussions under each video on Khan Academy, I know this one too https://www.physicsforums.com/, and this one in French https://zestedesavoir.com/forums/savoirs/sciences/

Re: So You Want to Learn Physics (2016)

#49
post #19

Bottom line is: work your ass off for at least 5 years, and maybe you'll have a chance to get it. At least, that's honest advice!

If you work hard for 5 years you will get it, it’s not a chance

Mmh maybe you can learn enough to understand what people are talking about generally, but there is no guarantee that you will be any good at it
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