I'm a chemical engineering student (just completed BS and am started the PhD program), but I'm very interested in particle physics as a hobby. I'm dismayed though with the sheer amount of information and math that is required to understand this stuff. I feel like a physicist could learn all of my engineering knowledge in a couple of weeks, but it would take years to learn concepts such as:

  • Gauge symmetry
  • Lagrangians, Hamiltonians
  • SUSY
  • Noether's theorem
  • Tensors
  • Feynman diagrams
  • General relativity
  • Standard model
  • Holographic principle

I don't even know what most of these things are -- I just see them in answers to questions, look them up on Wikipedia, glaze over at all the math I've never heard of, and continue on just as confused as before.

And it's not that I'm bad at math either -- I scored quite well on the AIME in high school. It's just that I've never learned these things (quaternions, spinors? No idea).

So when do most physics students learn concepts like this? Undergrad, grad school?

  • $\begingroup$ I learned Hamiltonian, Tensors and Lagrangian on 2nd class. Our optional-particle physics (Feynmann?) can be taken at 3rd class $\endgroup$ Aug 30, 2012 at 20:32
  • $\begingroup$ Unfortunately, there is no escaping the mathematics necessary to understand field theory. I'd suggest starting out by organizing your study in terms of "mathematical tools" and "physical theories". You will need the latter for a deeper understanding of the former. My suggestion would be to start with Group Theory (Abstract Algebra) and go from there. $\endgroup$ Aug 30, 2012 at 22:21
  • $\begingroup$ How much do you want to know? It's possible to learn these concepts at different levels of understanding: undergrads get the basic concepts, graduate students add the complications, and researchers at the bleeding edge follow the rabbit hole as far as it'll go. What's your goal? $\endgroup$
    – mng
    Aug 30, 2012 at 22:44
  • $\begingroup$ For information about books, see this question. $\endgroup$
    – David Z
    Aug 31, 2012 at 0:36
  • $\begingroup$ People who diagree with this recent change in policies, which disallows questions about any study material and references (papers) or education, instigated by David Zaslavsky and a few other powerful people without the whole community having a saying about it, you should have a look at this meta thread and vote accordingly. There are some people who disagree with these new policies, but they are not powerful enough. Study material/reference questions should exactly be allowed for the site to be useful for students and researchers in physics. $\endgroup$
    – Dilaton
    Apr 15, 2013 at 10:19

1 Answer 1


Dont be scared, there is not much to know. People create lots of information when they dont understand things, the moment good theory is discovered all facts become easily described through small number of ideas.

Start from this book - Halzen & Martin - "Quarks and Leptons: Introductory Course in Modern Particle Physics". By the time you will master it you will be better than average particle physics postdoc. Forget string theory stuff its not relevant for the real data. All REAL knowledge of particle physics is summed up in this book (online version): http://pdglive.lbl.gov/listings1.brl?quickin=Y


  • 1
    $\begingroup$ I've deleted the comment discussion, since it became argumentative very quickly. $\endgroup$
    – David Z
    Aug 31, 2012 at 0:35
  • $\begingroup$ This answer is still unnecessary confrontative, even though the online book linked to may be interesting. That is the reason for my downvote. $\endgroup$
    – Dilaton
    Aug 31, 2012 at 16:04

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