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So You Want to Learn Physics (2016)

susanjfowler.com

71–80 of 126 posts

Re: So You Want to Learn Physics (2016)

#71

The author recommends some interesting popular books: 1. The Feynman Lectures on Physics 2. The Character of Physical Law by Richard Feynman 3. Deep Down Things: The Breathtaking Beauty of Particle Physics by Bruce Schumm 4. The Particle Odyssey by Frank Close 5. Weinberg's The First Three Minutes IMO someone who seriously wants to learn physics should read these books after they have gone through the typical undergr…

The Feynman lectures were specially designed for creme de la creme undergrads who already did a course in physics in high school. They are a terrible way for a noob to try to learn. Also strange that the author warns against exotic topics and then 3/5 of these recommendations are exotic things 99.9% of readers will never encounter.

They're definitely aimed at the type of student who gets into Caltech. My general advice would be to give them a go if you're interested, because they're wonderful, but be open to switching to other texts if it's not working so well.

I kind of think the whole OP should be subject to the same caveat: Susan Fowler is probably not just hardworking but very very smart, and you shouldn't necessarily expect comparable results. It may go like the guy who tried to become a golf pro on the 10,000-hours theory: https://en.wikipedia.org/wiki/Dan_McLaughlin_(golfer)

Re: So You Want to Learn Physics (2016)

#72
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…

The holographic universe is another popular one. We have some similar things in mathematics (e.g. anything to do with Godel).

I think, though, that if you want to understand physics, it probably makes sense to devote some of your time to understanding what physicists are excited about.

I have a feeling (and this is heavy speculation) that a lot of strong physicists were fed on pop physics and science fiction before they learned the hard science. This helps approach the subject with an inborn curiosity, which can focus your attention when learning technical subjects.

Pop physics books may not be the ideal way to do this, but it's probably better than nothing at all.

Re: So You Want to Learn Physics (2016)

#73

A few more good pop physics books: Maxwell - Matter and motion. Written by THE Maxwell, what more do you need to know? long out of copy-write and available on the web for free Born - The restless universe. discusses atomic theory and describes some of the more down to earth parts of quantum theory, especially how the theory explains quantitative properties of atoms and the periodic table. Einstein & Infeld - The evol…

A bit more on the Maxwell book: it's a real textbook rather than "pop physics" in the usual sense, but written for people with only a high-school level of math (algebra and geometry). Wonderful explanations -- for one, iirc, the derivation of Kepler's conic-section law which Feynman later rediscovered and presented in "The Motion of Planets Around the Sun" -- although the prose style is rather stuffy and Victorian, a…

Are you sure we're thinking of the same book? The one i'm referring to [1] uses basic algebra (fractions, exponents, variables), only a couple of times in the entire exposition if i remember correctly. Its precisely what I would think of as good, non-fake popular physics. Edit: On second thought, I suppose this really isn't "popular physics in the usual sense" as you described it, so we probably are referring to the same text!

https://archive.org/details/in.ernet.dli.2015.151311/page/n7

Re: So You Want to Learn Physics (2016)

#74
post #54

Earlier quoted context omitted.

> all this crazy complicated and far-fetched ideas, rather than simple and beautiful principles to understand reality Would you mind giving some examples of what kind of "simple and beautiful principles" you have in mind?

Depends on the level (and I am just giving some examples): - Advanced high school: You can use conservation of energy or other "conservation laws" as a guiding principle. This lets you solve a problem with just a couple of lines of simple algebra. On the other hand, using the "naive" approach of studying the forces that act on the system would require heavy algebra and some calculus. - College: Instead of calculating…

> Conservation laws are actually consequences of symmetries.

For those unfamiliar, this is essentially the content of Noether's Theorem[0]. One of many beautiful contributions of Emmy Noether.

I've heard several physicists describe it as one of the most beautiful theorems in physics.

[0] https://en.wikipedia.org/wiki/Noether%27s_theorem

Re: So You Want to Learn Physics (2016)

#75
For more advanced topics, this is an amazing book that covers many graduate topics in a unified and consistent notation: https://www.amazon.ca/dp/0691159025

Draft of the book is available here for free: http://www.pmaweb.caltech.edu/Courses/ph136/yr2012/

Warning: this is very advanced material... I'm still on Chapter 1.

Re: So You Want to Learn Physics (2016)

#76
post #25
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…

> "11 dimensions", "string theory", or "time dilation" One of these things is not like the others...

The derivative of time in the spacetime* tensor is just 1. There's no speed up, locally, which is what counts. The rest is just an effect of observation.

*I do not remember nor care what it's called. I'm sure you know what I mean anyway.

Re: So You Want to Learn Physics (2016)

#77
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!

Well, this depends on the level on which you want to be. A good way to start is with an elementary (i.e. non-calculus based) physics course. Despite being called "elementary," it might get you a long way towards learning a lot of non-trivial, often quite complex - and useful - physics. This could take a few months to a year. It will introduce you to vector algebra and the practical use of trigonometry. The next round would be a "general" course. It is the best chance to learn much of the "high-end" physics a "normal" person or an engineer will ever have. This course uses some simple ways of doing calculus and vector analysis, much of which will be explained as you go. Be prepared to spend a couple of years on this course. After that, you could cut your teeth into a traditional course on theoretical physics (e.g. Landau and Lifschitz). Not many people will end up there, and there may be little practical benefit for most of us. This course will require much of the traditional higher math. There is no telling how many years and how big an effort you will have to devote to this. And, finally, there's the "modern" theoretical physics, which is heavily based on modern (abstract) mathematics - very cool stuff indeed!

Re: So You Want to Learn Physics (2016)

#78

Earlier quoted context omitted.

A bit more on the Maxwell book: it's a real textbook rather than "pop physics" in the usual sense, but written for people with only a high-school level of math (algebra and geometry). Wonderful explanations -- for one, iirc, the derivation of Kepler's conic-section law which Feynman later rediscovered and presented in "The Motion of Planets Around the Sun" -- although the prose style is rather stuffy and Victorian, a…

Are you sure we're thinking of the same book? The one i'm referring to [1] uses basic algebra (fractions, exponents, variables), only a couple of times in the entire exposition if i remember correctly. Its precisely what I would think of as good, non-fake popular physics. Edit: On second thought, I suppose this really isn't "popular physics in the usual sense" as you described it, so we probably are referring to the…

Yes, that's the one.

Re: So You Want to Learn Physics (2016)

#79
As a new-comer to the topic of manifolds, learning it from math textbooks is painful. That seems to be the case even if you're reasonably strong at analysis, topology and linear algebra. I find textbooks written for theoretical physicists much gentler read. Physics textbooks can be a good place to start learning, say, differential geometry even if you don't care about physics (I don't).

Re: So You Want to Learn Physics (2016)

#80

The author recommends some interesting popular books: 1. The Feynman Lectures on Physics 2. The Character of Physical Law by Richard Feynman 3. Deep Down Things: The Breathtaking Beauty of Particle Physics by Bruce Schumm 4. The Particle Odyssey by Frank Close 5. Weinberg's The First Three Minutes IMO someone who seriously wants to learn physics should read these books after they have gone through the typical undergr…

The Feynman lectures were specially designed for creme de la creme undergrads who already did a course in physics in high school. They are a terrible way for a noob to try to learn. Also strange that the author warns against exotic topics and then 3/5 of these recommendations are exotic things 99.9% of readers will never encounter.

>Also strange that the author warns against exotic topics and then 3/5 of these recommendations are exotic things 99.9% of readers will never encounter.

I don't think you understand what "exotic" means in this context. Literally everything on this list except QFT is something pretty much every physicist will study. (And every theorist will study QFT.) No coincidence that it's almost topic for topic what I studied in grad school. This is "how to actually learn physics", not "how to learn a subset of physics."

Exotic topics would be quantum loop gravity or supersymmetry; things which sound cool but aren't foundational in the same way.

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