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For the love of God, don't use Feynman lectures to learn physics. That's something you read after you know physics, for relaxation and conceptual stuff. Resnick

For the love of God, don't use Feynman lectures to learn physics. That's something you read after you know physics, for relaxation and conceptual stuff. Resnick & Halliday is a much better freshman/sophomore book. Susskind's "theoretical minimum" is actually pretty good. http://theoreticalminimum.com/courses http://theoreticalminimum.com/courses Fowler gives a pretty conventional undergraduate physics curriculum (adding Feynman in there somehow). If it were me: learn the math tools first. I assume you know linear algebra; learn differential equations. From there, go straight to higher level books. There's very little difference in undergraduate vs graduate quantum mechanics and E&M other than the math is slightly more sophisticated in grad school. Might as well do it right. Messiah for QM and Jackson for E&M. Classical mechanics, the tradition is to learn Lagrangian mechanics in high level undergrad and Hamiltonian in grad school. There's no real reason to do it in this order, and a decent reason (understanding Quantum) to do it in reverse order. Amusingly, the math is cleaner in Hamiltonian mechanics, but you may find yourself unable to do some simple problems you can do with Newtonian physics; so this will be a weird working backward thing. Stat Mech, I think you should just read Reif; skip Ma or whatever they use in grad school now. FWIIW I know/knew people who did this: started grad school without having done any undergrad courses in physics. I think skipping a lot of the introductory stuff, and visiting it later is actually better. The rest of it can be done with the same machinery you learned in QM, E&M, Mechanics and Stat Mech. Max leverage if you had to pick one: probably classical mechanics for a DL guy, E&M for general knowledge of tools. I'd suggest not actually trying to simulate physical systems on a computer: you probably stare at computers too much anyway.

thinkr42 7y ago
"For the love of God, don't use Feynman lectures to learn physics. That's something you read after you know physics, for relaxation and conceptual stuff..." Agree with this 100%. To learn math or physics you have to do it, experiment, and all that.
- beezle 7y ago
  Feynman lectures are fine as a supplement to more standard text.
gaze 7y ago
HRK is for learning physics, feynman is for feeling like you're learning physics when you aren't, and ll is for feeling like you're understanding nothing. LL and Feynman are definitely nice to look back upon though.
- madhadron 7y ago
  L&L assumes a particular set of steps and shared reading culture. I had the good fortune to have a professor take me through volume 1 in a classical mechanics class. Thereafter other volumes became very straightforward to read and taught me a lot of physics.
  - gaze 7y ago
    Yeah I think that's right. LL is now something I look back upon frequently for reference... but you have to have been introduced properly.
petermcneeley 7y ago
"I'd suggest not actually trying to simulate physical systems on a computer" I cannot disagree enough with this statement. I am double major in Physics and CS. There are two kinds of physics, Math and Physics. Most of what you learn in uni physics is Math. But the Math is only one (outdated) description of the nature of physical law. Leonard Susskind himself has said on multiple occasions that the equations of physics are at most highschool math however the solutions are sometimes phd+ level. To me Physics is the study of the relationship between state. Mostly this state is finite and the laws governing its evolution are simple and local. A computer is the best tool to discover the solutions to this evolving state.
- ukj 7y ago
  I am to really glad to hear commentary like this coming from physicists. (read: glad to see others siding with my biases). Ceteris paribus there is one significant distinction between Mathematics and Computer Science: state. The Mathematical Universe is immutable/stateless/timeless. The Computational Universe is mutable/stateful/time-bound. The observer effect in physics can be trivially expressed and evaluated as a mutating getter in any programming language. It cannot be expressed in any Mathematical grammar.
  - davidivadavid 7y ago
    It seems likely that anything that can be expressed in "any programming language" is isomorphic to something that exists in math and can be expressed in that language (automata theory, type theory, category theory, pick your poison).
    - ukj 7y ago
      That is probably because you think expression end evaluation are isomorphic. They aren't. Not all functions are referentially transparent. All Mathematical functions are assumed to be.
      - deleted 7y ago
        [deleted]
rguzman 7y ago
context: former theoretical physics grad student, dropped out ABD to start a company. this comment is right on the money on several fronts: - the Feynman lectures are great after you already understand some of the mechanics of "doing" physics and have some other exposure to the topics, Halliday & Resnick is a better place to start on any one topic - with infinite time, i'd always follow the approach of learning the math first and then the physics, the book by Boas is pretty good for self study of the minimum necessary math - there's no real reason to follow a traditional grad school curriculum ala Fowler unless you need to pass quals in a traditional grad school setting - simulating physical systems on computers is a pretty good exercise, but very time-consuming, avoid if you already spend a lot of time in front of computers and some thoughts of my own: - "get a strong foundation in Physics" is a bit too vague to be a useful goal, some examples of potentially better goals: "be able to pass a classical mechanics qual in the allotted time", "be able to write down the standard model and explain it", "be able to grok N papers from the X section of arxiv per week", "be able to write down toy classical field theories and calculate their predictions", ... - if you are looking to avoid computers, try supplementing your reading with simple experiments either by buying educational kits or by hacking together things - the books by David Griffiths (esp the E&M one) are awesome - try to follow curiosity instead of a program: trying to answer "how do superconducting materials work?" for yourself is better than "follow the grad intro to condensed matter that's available online" - use the physics stackexchange and other forums: asking and answering questions can be very helpful
- psalminen 7y ago
  Second Griffiths books, I used both his E&M and QM books in undergrad. His voice is excellent.
- godelski 7y ago
  I'll second Griffiths for E&M, Quantum, and Particle. I think everyone that has gone through a physics undergrad will swear by Griffiths. He is just such a delight. But I'll suggest Marion and Thornton [0] for Classical. With Griffiths for E&M and Thornton for Classical you should be able to get a really good grasp on most of "physics". I'll also say that these series are upper division for undergrads. Given OP's background I think these would be fine starting points. If not, start with Halliday[1]. For grad level, the gold standard is Goldstein for Classical [2] and Jackson for Electrodynamics[3]. These types of books will give you a very strong base in physics and should enable you to branch out. Given your ML background you may be very interested in thermodynamics and statistical mechanics. I'll also add an "out there" idea. Sign up for physics classes at your local community college if they offer labs. I say this as someone who went Physics -> CS and is doing HPC + ML. Labs really stress and force you to do analysis. Lower division labs won't ask too much, but if you go in with this intent I think you can get a lot out of it. I'm sure that if you did these lower div labs and talked to a professor at your local uni they would allow you to sit in on upper division labs (you would NEED to show that you are serious first, because these labs can be dangerous! Happy to help you learn doesn't mean happy to babysit and make sure you don't electrocute yourself or making sure you don't take a laser to the eye. TAing undergrad labs I saw enough people get electrocuted, including myself... more than once). [0] https://smile.amazon.com/Classical-Dynamics-Particles-Systems-Thornton/dp/0534408966 https://smile.amazon.com/Classical-Dynamics-Particles-System... [1] https://www.smile.amazon.com/Fundamentals-Physics-10th-David-Halliday-ebook/dp/B07889MJMT https://www.smile.amazon.com/Fundamentals-Physics-10th-David... [2] https://smile.amazon.com/Classical-Mechanics-Goldstein-Poole-Safko/dp/8177582836 https://smile.amazon.com/Classical-Mechanics-Goldstein-Poole... [3] https://smile.amazon.com/Classical-Electrodynamics-Third-David-Jackson/dp/047130932X/ https://smile.amazon.com/Classical-Electrodynamics-Third-Dav...
Koshkin 7y ago
I found the "no-nonsense" series of books on elementary theoretical physics by Jakob Schwichtenberg to be pretty good as a complement to Susskind's.
AnthonBerg 7y ago
We all learn differently. Please don't deal in pedagogical certainties that may close doors unventured. Feynman's lectures were crucially eye-opening for me and many others.
- ska 7y ago
  It's pretty well established now that Feynman is not a good general approach for introductory physics. Plenty of talented teachers have tried it, and moved on to something more effective. This doesn't contradict your point. A particular individual may find them very helpful in learning and understanding the foundational stuff. By all means try, and if it works for you, great. However, it shouldn't be at the top of anyone's list of things to try first. And if you have tried, and it didn't work well for you - it's not you.
  - AnthonBerg 7y ago
    Exactly. I ask that the applicability of Feynman’s lectures is not presented in absolutes - not always, not for everyone, not never. But definitely sometimes for some. Including to start with. They’re quite beautiful.
  - gowld 7y ago
    > Plenty of talented teachers have tried it, and moved on to something more effective. Including, you know, Richard Feynman.
  - stared 7y ago
    > It's pretty well established now that Feynman is not a good general approach for introductory physics. Citation needed. For people at the Physics Olympiad level, it is hard to find something as eye-opening and insightful as Feynman Lectures on Physics. For more "general audience", I guess that a more step-by-step is preferred. I know many people (usually not the Olympiad tribe) who preferred Halliday & Resnick.
    - dtornabene 7y ago
      I'm a logician and the Feynman lectures were incomprehensible when I tried to work through them. I for one am glad to see people pushing students toward more approachable texts.
nearmuse 7y ago
So far, they seem like a good way of reconnecting odd pieces of university program scattered around in my head. Maybe from scratch, they do not have enough math and overexplain some stuff. What are the usual arguments against this though?
propter_hoc 7y ago
I can't believe I am reading a recommendation that someone with little background in E&M self-studies with Jackson. That book is incredibly difficult even with a great graduate-level professor.
- throwqwerty 7y ago
  academic virtue signaling. like people recommending TAOCP to people that don't know how to program or rudin (either one!) to people that don't know any math.
  - hriir0 7y ago
    Interesting. To me that’s just a subjective list the author likes. The replies seem a bit on the level of “...but everyone knows really.” I always took notions like “expert” virtue signaling to mean experts seem convinced we should all learn via the timelines they did. Uni students versed in textbook physics, linear timelines for learning cause that’s how society taught them, are also experts in working cognitive theories. Incredible.
    - throwqwerty 7y ago
      >To me that’s just a subjective list the author likes. but the prompt isn't "list some books you like" but "how should I learn" so there's obviously intent in picking those books.
      - hriir0 7y ago
        “Likes for learning” is not an unreasonable acquiescence for the reader to consider. English is a terrible language and taking how we use it so literally is as bad as the language itself.
- xzel 7y ago
  +1. The Jackson book is notoriously difficult. I think Griffith's book might be better for a self-learner but, iirc, and I haven't read the book in more than 10 years now, he expects a pretty good understanding of applied calculus before you open the book, so read up on that! Best of luck with the studies OP. Also, the look into the Feynman book QED once you have a little bit under your belt. Its a fun and pretty short read and there isn't much math at all. I also think its a fun thing to read while learning EM since it opens you mind up to the next subject down the line, QED.
stared 7y ago
This piece of advice is wrong on so many levels, from the general context. I cannot believe it got 1st place here. (I got a Ph.D. in theoretical quantum optics, and I do have over a decade of experience teaching gifted high-school students. There is a lot of experience that works, and doesn't work, on people without prior background.) Feynman Lectures are much a more lively, insightful, overview of physics (I started reading when I was 14 or 15 y.o.; jumped there after reading one advanced high-school textbook). While I do know people who preferred Halliday & Resnick, these were people who liked a more straightforward, even if less insightful or colorful, approach. > learn the math tools first. Nope. You can spend 2 years (not a joke) to get mathematics to prove Stokes theorem, in one of the more general versions. Or draw a few cubes and squares, and get there is 15 mins or so. For regular 1 dim integrals, it is a one year course of mathematical analysis, if you want to do it rigorously. For many tools (e.g. Fenman Path Integrals) there is no rigorous math approach that is in use (at all). While, sure, you need to continuously improve your mathematical skills, my strong suggestion is first physics, then maths. Same Dirac Delta first as a trick, only later (and if you wish for math's sake) learn about distributions, Radon measures, etc. For E&M: for introduction, totally start with Griffiths. It is much more approachable as the introduction. > There's very little difference in undergraduate vs graduate quantum mechanics. I don't know where to get started, but it is nor true. For quantum information - yes, you can start with undergraduate maths. For anything going into quantum field theory, you would need to know much more about Lagrangian mechanics, group representations, symmetries, differential geometry, etc.
- scottlocklin 7y ago
  > You can spend 2 years (not a joke) to get mathematics to prove Stokes theorem, in one of the more general versions. You're out of your mind. You don't need to prove Gauss-Stokes in the general version to understand Maxwell's equations; you just need 3-d calculus, and you're done. Bike shedding the process further is silly: I could claim you don't really understand GR (or for that matter, E&M) without Hatcher-level understanding of Algebraic topology. All you need is the simple calculus theorem, such as is presented in Jackson. > For anything going into quantum field theory.... This is a rubbish argument: yes, you need more math to do quantum field theory. You also need basic quantum mechanics first, which is what I'm talking about for a self study program. If you want to go on to fiddle with QED, you can fool around with Itzykson and Zuber (and Griffiths book) later, when you actually know how non-relativistic QM works, and how relativity works. First learn basic Schroedinger stuff and something like S-matrix theory. Don't learn the shitty undergrad training wheels crapola; do the real thing. That's my advice in general. If you work your way through a differential equations book; there is no point in doing the intermediate stuff and a great argument (it's a waste of time; a make work program for physics professors, and a weeder for people with low dedication to the subject) for skipping it. FWIIW I was not a theorist, though I had some theory papers queued up on quantum dynamics. I think what everyone knows after first year of grad school is a pretty good basket of knowledge, which is why the 1st year grad school program is virtually identical everywhere in the world. It's like a gentleman learning Latin in the old days. There is a direct line from advanced calculus to completed first years of grad school physics; one which I outlined above. The imbecile make-work program of doing a bunch of intermediate problems in junior and senior year; it's really not worth it if you're an adult with a functioning cerebral cortex. Or if you're trying to pass prelims/GREs which test you on these subjects. Otherwise; skip it -do the important bits, and revisit the training wheels versions later when you need them. That's all.

thinkr42 7y ago

"For the love of God, don't use Feynman lectures to learn physics. That's something you read after you know physics, for relaxation and conceptual stuff..." Agree with this 100%. To learn math or physics you have to do it, experiment, and all that.

beezle 7y ago
Feynman lectures are fine as a supplement to more standard text.

gaze 7y ago

HRK is for learning physics, feynman is for feeling like you're learning physics when you aren't, and ll is for feeling like you're understanding nothing. LL and Feynman are definitely nice to look back upon though.

madhadron 7y ago
L&L assumes a particular set of steps and shared reading culture. I had the good fortune to have a professor take me through volume 1 in a classical mechanics class. Thereafter other volumes became very straightforward to read and taught me a lot of physics.
- gaze 7y ago
  Yeah I think that's right. LL is now something I look back upon frequently for reference... but you have to have been introduced properly.

petermcneeley 7y ago

"I'd suggest not actually trying to simulate physical systems on a computer" I cannot disagree enough with this statement. I am double major in Physics and CS. There are two kinds of physics, Math and Physics. Most of what you learn in uni physics is Math. But the Math is only one (outdated) description of the nature of physical law. Leonard Susskind himself has said on multiple occasions that the equations of physics are at most highschool math however the solutions are sometimes phd+ level. To me Physics is the study of the relationship between state. Mostly this state is finite and the laws governing its evolution are simple and local. A computer is the best tool to discover the solutions to this evolving state.

ukj 7y ago
I am to really glad to hear commentary like this coming from physicists. (read: glad to see others siding with my biases). Ceteris paribus there is one significant distinction between Mathematics and Computer Science: state. The Mathematical Universe is immutable/stateless/timeless. The Computational Universe is mutable/stateful/time-bound. The observer effect in physics can be trivially expressed and evaluated as a mutating getter in any programming language. It cannot be expressed in any Mathematical grammar.
- davidivadavid 7y ago
  It seems likely that anything that can be expressed in "any programming language" is isomorphic to something that exists in math and can be expressed in that language (automata theory, type theory, category theory, pick your poison).
  - ukj 7y ago
    That is probably because you think expression end evaluation are isomorphic. They aren't. Not all functions are referentially transparent. All Mathematical functions are assumed to be.
    - deleted 7y ago
      [deleted]

rguzman 7y ago

context: former theoretical physics grad student, dropped out ABD to start a company. this comment is right on the money on several fronts: - the Feynman lectures are great after you already understand some of the mechanics of "doing" physics and have some other exposure to the topics, Halliday & Resnick is a better place to start on any one topic - with infinite time, i'd always follow the approach of learning the math first and then the physics, the book by Boas is pretty good for self study of the minimum necessary math - there's no real reason to follow a traditional grad school curriculum ala Fowler unless you need to pass quals in a traditional grad school setting - simulating physical systems on computers is a pretty good exercise, but very time-consuming, avoid if you already spend a lot of time in front of computers and some thoughts of my own: - "get a strong foundation in Physics" is a bit too vague to be a useful goal, some examples of potentially better goals: "be able to pass a classical mechanics qual in the allotted time", "be able to write down the standard model and explain it", "be able to grok N papers from the X section of arxiv per week", "be able to write down toy classical field theories and calculate their predictions", ... - if you are looking to avoid computers, try supplementing your reading with simple experiments either by buying educational kits or by hacking together things - the books by David Griffiths (esp the E&M one) are awesome - try to follow curiosity instead of a program: trying to answer "how do superconducting materials work?" for yourself is better than "follow the grad intro to condensed matter that's available online" - use the physics stackexchange and other forums: asking and answering questions can be very helpful

psalminen 7y ago
Second Griffiths books, I used both his E&M and QM books in undergrad. His voice is excellent.
godelski 7y ago
I'll second Griffiths for E&M, Quantum, and Particle. I think everyone that has gone through a physics undergrad will swear by Griffiths. He is just such a delight. But I'll suggest Marion and Thornton [0] for Classical. With Griffiths for E&M and Thornton for Classical you should be able to get a really good grasp on most of "physics". I'll also say that these series are upper division for undergrads. Given OP's background I think these would be fine starting points. If not, start with Halliday[1]. For grad level, the gold standard is Goldstein for Classical [2] and Jackson for Electrodynamics[3]. These types of books will give you a very strong base in physics and should enable you to branch out. Given your ML background you may be very interested in thermodynamics and statistical mechanics. I'll also add an "out there" idea. Sign up for physics classes at your local community college if they offer labs. I say this as someone who went Physics -> CS and is doing HPC + ML. Labs really stress and force you to do analysis. Lower division labs won't ask too much, but if you go in with this intent I think you can get a lot out of it. I'm sure that if you did these lower div labs and talked to a professor at your local uni they would allow you to sit in on upper division labs (you would NEED to show that you are serious first, because these labs can be dangerous! Happy to help you learn doesn't mean happy to babysit and make sure you don't electrocute yourself or making sure you don't take a laser to the eye. TAing undergrad labs I saw enough people get electrocuted, including myself... more than once). [0] https://smile.amazon.com/Classical-Dynamics-Particles-Systems-Thornton/dp/0534408966 https://smile.amazon.com/Classical-Dynamics-Particles-System... [1] https://www.smile.amazon.com/Fundamentals-Physics-10th-David-Halliday-ebook/dp/B07889MJMT https://www.smile.amazon.com/Fundamentals-Physics-10th-David... [2] https://smile.amazon.com/Classical-Mechanics-Goldstein-Poole-Safko/dp/8177582836 https://smile.amazon.com/Classical-Mechanics-Goldstein-Poole... [3] https://smile.amazon.com/Classical-Electrodynamics-Third-David-Jackson/dp/047130932X/ https://smile.amazon.com/Classical-Electrodynamics-Third-Dav...

Koshkin 7y ago

I found the "no-nonsense" series of books on elementary theoretical physics by Jakob Schwichtenberg to be pretty good as a complement to Susskind's.

AnthonBerg 7y ago

We all learn differently. Please don't deal in pedagogical certainties that may close doors unventured. Feynman's lectures were crucially eye-opening for me and many others.

ska 7y ago
It's pretty well established now that Feynman is not a good general approach for introductory physics. Plenty of talented teachers have tried it, and moved on to something more effective. This doesn't contradict your point. A particular individual may find them very helpful in learning and understanding the foundational stuff. By all means try, and if it works for you, great. However, it shouldn't be at the top of anyone's list of things to try first. And if you have tried, and it didn't work well for you - it's not you.
- AnthonBerg 7y ago
  Exactly. I ask that the applicability of Feynman’s lectures is not presented in absolutes - not always, not for everyone, not never. But definitely sometimes for some. Including to start with. They’re quite beautiful.
- gowld 7y ago
  > Plenty of talented teachers have tried it, and moved on to something more effective. Including, you know, Richard Feynman.
- stared 7y ago
  > It's pretty well established now that Feynman is not a good general approach for introductory physics. Citation needed. For people at the Physics Olympiad level, it is hard to find something as eye-opening and insightful as Feynman Lectures on Physics. For more "general audience", I guess that a more step-by-step is preferred. I know many people (usually not the Olympiad tribe) who preferred Halliday & Resnick.
  - dtornabene 7y ago
    I'm a logician and the Feynman lectures were incomprehensible when I tried to work through them. I for one am glad to see people pushing students toward more approachable texts.

nearmuse 7y ago

So far, they seem like a good way of reconnecting odd pieces of university program scattered around in my head. Maybe from scratch, they do not have enough math and overexplain some stuff. What are the usual arguments against this though?

propter_hoc 7y ago

I can't believe I am reading a recommendation that someone with little background in E&M self-studies with Jackson. That book is incredibly difficult even with a great graduate-level professor.

throwqwerty 7y ago
academic virtue signaling. like people recommending TAOCP to people that don't know how to program or rudin (either one!) to people that don't know any math.
- hriir0 7y ago
  Interesting. To me that’s just a subjective list the author likes. The replies seem a bit on the level of “...but everyone knows really.” I always took notions like “expert” virtue signaling to mean experts seem convinced we should all learn via the timelines they did. Uni students versed in textbook physics, linear timelines for learning cause that’s how society taught them, are also experts in working cognitive theories. Incredible.
  - throwqwerty 7y ago
    >To me that’s just a subjective list the author likes. but the prompt isn't "list some books you like" but "how should I learn" so there's obviously intent in picking those books.
    - hriir0 7y ago
      “Likes for learning” is not an unreasonable acquiescence for the reader to consider. English is a terrible language and taking how we use it so literally is as bad as the language itself.
xzel 7y ago
+1. The Jackson book is notoriously difficult. I think Griffith's book might be better for a self-learner but, iirc, and I haven't read the book in more than 10 years now, he expects a pretty good understanding of applied calculus before you open the book, so read up on that! Best of luck with the studies OP. Also, the look into the Feynman book QED once you have a little bit under your belt. Its a fun and pretty short read and there isn't much math at all. I also think its a fun thing to read while learning EM since it opens you mind up to the next subject down the line, QED.

stared 7y ago

This piece of advice is wrong on so many levels, from the general context. I cannot believe it got 1st place here. (I got a Ph.D. in theoretical quantum optics, and I do have over a decade of experience teaching gifted high-school students. There is a lot of experience that works, and doesn't work, on people without prior background.) Feynman Lectures are much a more lively, insightful, overview of physics (I started reading when I was 14 or 15 y.o.; jumped there after reading one advanced high-school textbook). While I do know people who preferred Halliday & Resnick, these were people who liked a more straightforward, even if less insightful or colorful, approach. > learn the math tools first. Nope. You can spend 2 years (not a joke) to get mathematics to prove Stokes theorem, in one of the more general versions. Or draw a few cubes and squares, and get there is 15 mins or so. For regular 1 dim integrals, it is a one year course of mathematical analysis, if you want to do it rigorously. For many tools (e.g. Fenman Path Integrals) there is no rigorous math approach that is in use (at all). While, sure, you need to continuously improve your mathematical skills, my strong suggestion is first physics, then maths. Same Dirac Delta first as a trick, only later (and if you wish for math's sake) learn about distributions, Radon measures, etc. For E&M: for introduction, totally start with Griffiths. It is much more approachable as the introduction. > There's very little difference in undergraduate vs graduate quantum mechanics. I don't know where to get started, but it is nor true. For quantum information - yes, you can start with undergraduate maths. For anything going into quantum field theory, you would need to know much more about Lagrangian mechanics, group representations, symmetries, differential geometry, etc.

scottlocklin 7y ago
> You can spend 2 years (not a joke) to get mathematics to prove Stokes theorem, in one of the more general versions. You're out of your mind. You don't need to prove Gauss-Stokes in the general version to understand Maxwell's equations; you just need 3-d calculus, and you're done. Bike shedding the process further is silly: I could claim you don't really understand GR (or for that matter, E&M) without Hatcher-level understanding of Algebraic topology. All you need is the simple calculus theorem, such as is presented in Jackson. > For anything going into quantum field theory.... This is a rubbish argument: yes, you need more math to do quantum field theory. You also need basic quantum mechanics first, which is what I'm talking about for a self study program. If you want to go on to fiddle with QED, you can fool around with Itzykson and Zuber (and Griffiths book) later, when you actually know how non-relativistic QM works, and how relativity works. First learn basic Schroedinger stuff and something like S-matrix theory. Don't learn the shitty undergrad training wheels crapola; do the real thing. That's my advice in general. If you work your way through a differential equations book; there is no point in doing the intermediate stuff and a great argument (it's a waste of time; a make work program for physics professors, and a weeder for people with low dedication to the subject) for skipping it. FWIIW I was not a theorist, though I had some theory papers queued up on quantum dynamics. I think what everyone knows after first year of grad school is a pretty good basket of knowledge, which is why the 1st year grad school program is virtually identical everywhere in the world. It's like a gentleman learning Latin in the old days. There is a direct line from advanced calculus to completed first years of grad school physics; one which I outlined above. The imbecile make-work program of doing a bunch of intermediate problems in junior and senior year; it's really not worth it if you're an adult with a functioning cerebral cortex. Or if you're trying to pass prelims/GREs which test you on these subjects. Otherwise; skip it -do the important bits, and revisit the training wheels versions later when you need them. That's all.