
So You Want to Learn Physics (2016) - happy-go-lucky
https://www.susanjfowler.com/blog/2016/8/13/so-you-want-to-learn-physics
======
andrepd
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 stick to the good ones that talk about the real physics we know exists.

Oh god yes. Why is it that whenever a lay person wants to talk about physics
they talk about "11 dimensions", "string theory", or "time dilation", or any
similarly crazy-sounding term that they read in a massively incorrect pop-sci
article. Basically it makes it sound like physics is about all this crazy
complicated and far-fetched ideas, rather than simple and beautiful principles
to understand reality, which is what it is.

I don't know if I managed to convey what I mean.

~~~
twtw
> 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?

~~~
krastanov
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 the path of a ray of light through some
inhomogeneous piece of transparent matter by doing some form of raytracing,
you can use Fermat's "minimization principle". They are equivalent, but a
rigorous definition of the minimization principle is a single sentence, while
the other approach takes a lot of work to express clearly.

\- Advanced college: Conservation laws are actually consequences of
symmetries. Instead of thinking in terms of a complicated expression for
energies and momenta, you can say that they are consequences of the fact that
the laws of the universe do not change from today to tomorrow.

Yes, the more simple and beautiful a principle is, the more abstract it is.
However, the simplicity and ease of working with it makes the abstraction
worth it.

Just like in C you can have your own weird struct that implements objects and
higher order functions, but using a functional or object oriented language
makes everything safer and easier and more readable.

~~~
SquishyPanda23
> 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](https://en.wikipedia.org/wiki/Noether%27s_theorem)

------
sleavey
I went to university intending to study computing science, but switched to
physics half way through under the assumption that you could teach yourself
computing science more easily than physics. I wouldn't change what I learned
for the world, and I'm now in physics academia, but it's funny how my job
these days involves using some of the algorithms, mathematics and data
structures that I was just about to start learning if I had stayed the course
in computing.

My few years of study and general interest in computing has already given me a
huge advantage in solving certain types of problem. I think computing science
(not just software engineering) is slowly but surely becoming an essential
part of many areas of modern physics research.

~~~
naasking
> I think computing science (not just software engineering) is slowly but
> surely becoming an essential part of many areas of modern physics research.

I like to say that physics, mathematics, and computer science are the three
pillars of human knowledge. There's some overlap between each pillar, and we
don't yet fully understand how each of them fully relate to the others, but
each is essential to gathering a full picture of any phenomenon.

~~~
lolitan
Wrong. Philosophy and Mathematics are the real pillars of knowledge.
Everything else can be derived from this including physics.

~~~
naasking
Philosophy doesn't really produce knowledge, it explores and frames questions.
When we accept that the questions define a coherent domain of discourse, we
create a field of study that does produce knowledge. This is how natural
philosophy became science, and if ethics ever gets to this point, we'll get a
moral science which will produce moral knowledge. Ethics doesn't currently
produce moral knowledge.

------
musgravepeter
>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...](http://nbodyphysics.com/blog/2015/02/28/learn-physics-with-this-
one-trick/))

~~~
commandlinefan
Calculus, too. I wonder about the author’s implication that she actually
worked every problem in all of those textbooks. I suppose it’s possible, but
it would take a decade, at least, if you were working full time (and forget
having any kind of a social life or, god forbid, a couple of kids).

------
nhkssol
> 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.

This is irritatingly common in economics also though with economics it's less
often speculation and more often simplification to the point that it becomes
misleading.

e.g. "black holes suck in matter around them". Many pop science physics books
will make black holes sound unique in the way they are able to attract matter
which misleads readers as it is just gravity being applied to a massive
object.

------
amelius
I'll just drop a link to Susskind's "Theoretical Minimum" course:

[https://theoreticalminimum.com/courses](https://theoreticalminimum.com/courses)

~~~
tobmlt
Gerard ’t Hooft goes here too I think:
[http://www.goodtheorist.science/](http://www.goodtheorist.science/)

Though I think Susskind's lectures and books are truly the best starting point
for say, an engineer who wants to go back and do physics from the ground up.

------
anonytrary
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 undergraduate university books
(classical, E&M, quantum, stat-mech, etc.) I would not recommend reading
popular books until after you already understand the basic ideas of physics.
Popular science books are like dessert.

~~~
fjsolwmv
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.

~~~
pge
I also recall hearing that as an undegrad curriculum, the lectures never
worked well (even when feynman himself was teaching them). His way of
understanding physics is beautiful but not intuitive for most people. I read
them after getting a degree in physics and it was fascinating to see his
approach precisely because it was so different (and elegant) than the way it
is typically taught, but I could not have understood them nearly as well if I
had not already learned the concepts in a more traditional way.

All that is to say- The Feynman lectures are wonderful, but I would not
recommend them as a first text.

~~~
derangedHorse
I disagree. As someone who doesn't know much about Physics, certain things I
read in the Feynman lectures today still stick with me. Like if you drop a
heavy object onto the floor, its temperature rises by a minuscule amount lol.

~~~
anonytrary
> Like if you drop a heavy object onto the floor, its temperature rises by a
> minuscule amount lol.

Tidbits like this are not a substitute for a working knowledge of physics. The
Feynman Lectures are not a substitute for undergraduate courses. You'll get
more out of the Feynman Lectures after completing the main undergraduate
courses.

~~~
derangedHorse
I'm not sure what you define as a 'working' knowledge of Physics, but to get
to a research level of physics requires more than a few introductory physics
course also. I'm not saying the Feynman lectures is a substitute for learning
any specific part of Physics, but it is useful for understanding basic
concepts and also understanding how those concepts can fit in to our everyday
lives.

What I disagreed about in the post I replied to was the position that it
wasn't "intuitive" or a good first text for beginners.

------
Tomte
Susan Fowler's life story totally impresses me.

She is world-renowned for MeToo/Time Person of the Year, but her achievements
in physics through sheer will and hard work, even though her upbringings did
not give her much in that direction, makes me think there is a movie in it.

~~~
minhazm423
what are her achievements in physics?

------
d--b
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!

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

~~~
d--b
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

------
ivan_ah
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](https://www.amazon.ca/dp/0691159025)

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

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

------
anton_tarasenko
Also Landau and Lifshitz, Course of Theoretical Physics.[1]

Released to public domain on archive.org:
[https://www.reddit.com/r/Physics/comments/1dmxq7/our_beloved...](https://www.reddit.com/r/Physics/comments/1dmxq7/our_beloved_landaulifshitz_books_are_available/c9s774y/)

[1]
[https://en.wikipedia.org/wiki/Course_of_Theoretical_Physics](https://en.wikipedia.org/wiki/Course_of_Theoretical_Physics)

------
nyc111
I'd like to say that Mach's Science of Mechanics is a timeless book and I
would recommend to anyone who hopes to like physics. It's so different than
modern textbooks. You get the feeling of learning new things as he explains
each phenomenon with simple mathamatics and often ingenious ways.

[https://www.cambridge.org/core/books/science-of-
mechanics/D8...](https://www.cambridge.org/core/books/science-of-
mechanics/D8A72D6443150FDB4820DCA339836EB2)

------
cyrusmith
Recommending Griffith to study quantum mechanics is just plain wrong. It's
inconsistent, have many gaps in the material. There's a book superior in many
regards to Griffith \- the "Quantum Mechanics: Concepts and Applications" by
Zettili.

~~~
Koshkin
There's an astonishingly large number of books on basic QM (only, perhaps,
comparable to the number of books about differential forms :). It is probably
because each author feels that something is missing or unclear or outdated in
all other books. And this is despite the fact that QM in its fundamental shape
has been complete since mid-1920s.

------
earthicus
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 evolution of physics. pseudo-Historical exposition
taking us from the mechanical universe to fields to quanta, and from Galilean
relativity to Einstein relativity.

Reichenbach - the philosophy of space and time. technically philosophy of
science, not pop science, from the logical positivist school of the Vienna
circle. very readable discussion of abstract mathematical geometry and various
relativity principles, if you don't mind skipping some of the more bloviating
bits.

Pask - Magnificent Principia. Fantastic overview of Newton's Magnum Opus,
although it doesn't give enough historical context to what newton was building
on. Assumes some knowledge of calculus.

~~~
abecedarius
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, and Feynman has him beat there.

~~~
earthicus
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](https://archive.org/details/in.ernet.dli.2015.151311/page/n7)

~~~
abecedarius
Yes, that's the one.

------
hintymad
To put things in perspective, Susan is incredibly talented. She went from
barely knowing high school math to enjoying advanced mathematical physics in
fewer than three years, which means in this three years, she learned Analysis
(not Steward Calculus, but at least Baby Rudin, mind you), Differential
Equations, Linear Algebra, Abstract Algebra that covers at least groups,
rings, and fields, Functional Analysis, Advanced Probability and Mathematic
Statistics, Differential Geometry, to say the least. Besides that, she also
needed to learn mechanics, E&M, Quantum Mechanics, and what not. She achieved
all these in her part time as she was majored in Psychology. What's even more
amazing is that she didn't find her latent talent until she went to college,
and she could immediately enjoy Feynman's textbook with almost zero background
in Physics!

Bravo! Bravo!

------
mp3player
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).

------
ArtWomb
Caught this video the other day on Youtube. It's a archival 1959 lecture from
MIT demonstrating light's wave particle duality. Using only a visible light
source, photo-multiplier, and oscilloscope. Just remarkably clear and simple.
It's amazing how much more the memory retains with a demo. And I can't help
but think quantum computing could be made accessible to a wide audience in
this way.

The Physics of Light (1959) John King-MIT-Electromagnetic Radiation

[https://www.youtube.com/watch?v=bnSH6YDFXfk](https://www.youtube.com/watch?v=bnSH6YDFXfk)

------
joeblau
This couldn't have come at a better time for me. I was listening to Kara
Swishers interview with Elon Musk[1] and he touched on lots of physics related
concepts related to all of his companies. The interview made me want to learn
more about physics.

[1] - [https://www.recode.net/2018/11/2/18053424/elon-musk-tesla-
sp...](https://www.recode.net/2018/11/2/18053424/elon-musk-tesla-spacex-
boring-company-self-driving-cars-saudi-twitter-kara-swisher-decode-podcast)

~~~
nyc111
Elon Musk talks about arguing from first principles and claims this is the
physics way without going into details. What else did he say about physics
that you liked?

~~~
joeblau
When he was going into the Boring companies tunneling evaluation trying to
figure out weather current tunneling tech was power constrained or heat
constrained. Also he mentioned the supersonic jet design that he has. There
were also some undertones with the Tesla Roadster, Tesla Pickup truck and
SpaceX BFR.

~~~
nyc111
Ok, thanks for giving details. But these can be classified more like
engineering issues. I don't know if you agree.

------
Breadmaker
The Mechanical Universe (1986) [video]
[https://news.ycombinator.com/item?id=17793483](https://news.ycombinator.com/item?id=17793483)

------
melling
Previous discussions:

[https://news.ycombinator.com/item?id=12691963](https://news.ycombinator.com/item?id=12691963)

[https://news.ycombinator.com/item?id=13684303](https://news.ycombinator.com/item?id=13684303)

------
mathgenius
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.

~~~
antt
>You will get stuck, mostly on trivial stuff. Then what do you do?

Find other books. There's a reason why university libraries have old editions
of the same books and very similar books on the same topic.

~~~
edanm
This is great and, in my experience, non-trivial advice. I often used to get
stuck on a mathematics textbook, and wouldn't know how to go forward. Turns
out, sometimes different textbooks covering the same topic will be much
better, or even just will be better for teaching one specific concept.

------
perlgeek
Having completed a graduate level Physics education, I can attest that the
selection of topics is solid.

(Can't comment on the books, I learned in a different language where other
books tend to be used).

~~~
Tomte
Assuming it's German, would you like to list some of your favorites?

I've noticed that I mostly read English textbooks on all kinds of subjects,
because it's easier to get recommendations on HN or sites like chicmath.

~~~
perlgeek
Oh, it's been a long time :-), but I'll try to dig through my memory.

I think I liked the Gerthsen, our Profs also recommended Demtröder, which was
OK, but somehow I never liked it as much.

In theoretical physics, Nolting and Fließbach were good -- though I cannot
remember which topic I learned from where.

I did my Diplomarbeit on spin transport in mesoscopic systems, and really
liked "Electronic Transport in Mesoscopic Systems" by Datta, which at the time
seemed to be the only accessible and clear writing on the subject.

Disclaimer: I tended to go to the lectures very regularly, and mostly learned
from there, so the books very mostly supplemental material for me.

------
anualvis
Is there a similar list for Mathmatics somewhere?

~~~
Tomte
Not for self-study, but still interesting:
[https://www.ocf.berkeley.edu/~abhishek/chicmath.htm](https://www.ocf.berkeley.edu/~abhishek/chicmath.htm)

------
ivan_ah
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/excerpts/noBSguide_v5_preview.pdf)

\-
[https://minireference.com/static/tutorials/conceptmap.pdf](https://minireference.com/static/tutorials/conceptmap.pdf)

\- condensed printable tutorial:
[https://minireference.com/static/tutorials/mech_in_7_pages.p...](https://minireference.com/static/tutorials/mech_in_7_pages.pdf)

\- reviews:
[https://www.amazon.com/dp/0992001005/noBSmathphys](https://www.amazon.com/dp/0992001005/noBSmathphys)

------
nyc111
> ...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. Galileo
was not a physicist in the modern sense of the word. Even Newton was not a
physicist but a natural philosopher. Physics today is a professional field. By
studying physics textbooks you will only gain enough knowledge to pass physics
exams. It's much better to go out and look at nature directly. If you need
specific mathematics just learn that part, solve your problem and move on. But
academic physics, as she clearly mentions,claims to build on previous
knowledge. This is the way of scholasticism. Scholastics claim that without
spending two years studying calculus you cannot invert a matrix. (Because they
make a living teaching you calculus.) This is not true. Knowledge is not
linear. I can study and learn matrix operations with zero calculus knowledge.
The opposite of scholasticism is just-in-time knowledge. Whatever I need I can
look it up.

But thanks for posting this. There are good resources in it.

~~~
BeetleB
I think I appreciate the point you are making, but you have gone a little too
far in making that point. I've gone through a physics education, and I can
attest that one can learn the material, be good at taking exams, and still do
a poor job of applying it to the real world.

The other extreme is as problematic, though. Knowing certain formalism in
mathematics can _really_ help in expressing a physics principle - and at times
it takes a fair amount of seemingly pointless formalism to get to that point.

>Scholastics claim that without spending two years studying calculus you
cannot invert a matrix. (Because they make a living teaching you calculus.)

I have no idea where this is coming from. In my education, we were taught
matrix inversion a full year before calculus. I've studied matrix inversion
multiple times in my academic career, and I don't remember calculus being
invoked once.

And to be frank, I'd be extremely wary of anyone claiming strong physics
knowledge without learning calculus. Physics gained by leaps and bounds after
calculus was introduced. It is the subject one can apply calculus most easily
to, and is perhaps the reason we know more physics than any other discipline
out there.

~~~
Koshkin
> _wary of anyone claiming strong physics knowledge_

Well, that depends. Faraday was a _great_ physicist (his claims, whatever they
may have been, notwithstanding).

~~~
BeetleB
Are you suggesting that Faraday did not know calculus?

~~~
Koshkin
According to Wikipedia, "his mathematical abilities, however, did not extend
as far as trigonometry and were limited to the simplest algebra."

