# Particle Theory

## A Primer On The Part 3 Exam For The CTP[edit]

This comes from a discussion with the Part III exam committee in Fall ’06, Bob Jaffe (chair), Barton Zweibach and Hong Liu. Many sample question come from questions during the 10 particle physics exams given during the ’06-’07 academic year, by this exam committee.

**Format:**
A one and a half to two hour oral exam given in the areas of either: a) particle
physics, b) nuclear physics or c) quantum computing. The exam taker is not allowed notes
or other materials/books.

**Style:**
The student is given a topic within their chosen field at least a week prior to
the scheduled exam time. This topic may be related to their current research, but that
discretion is left for the committee. The student is expected to prepare a short presentation
on the topic, no more than 15 minutes long. The committee will ask questions throughout,
both related to the topic given, as well additional subjects within the field.

**Content:**

1. Basic quantum field theory. Interactions, Feynman diagrams and rules, renormalization, beta-functions.

2. The Standard Model. SU(3)xSU(2)xU(1), particle content, terms within the Lagrangian, interactions, symmetries.

3. SU(2)xU(1), EW sector. Higgs mechanism, symmetry breaking, mass generation for fermions and gauge bosons, CKM matrix, massive neutrinos/PMNS matrix.

4. SU(3) Color sector. Asymptotic freedom/confinement, Theta-vacua/strong CP problem, the quark model/octets and decuplets, deep inelastic scattering/form factors, Bjorken scaling, anomalies.

5. Effective theories. Non-linear sigma model and other pion models, higher dimensional operators and how they impact symmetries in the SM.

6. Beyond the SM. Student should be familiar with the problems within the SM and some of their theoretical solutions. GUTs, SUSY, extra dimensions, string theory, landscapes. This knowledge should be of the level of talks given at the CTP.

7. Experiment. Student should be familiar with the evidence for the SM, but is not required to memorize specific details. The level should be that of a colloquia talk.

8. Cosmology and it’s relation to particle physics. Dark matter & Dark energy, possible resolutions within the current theoretical framework. Again, the knowledge expected is at a colloquia level.

**Good study materials:** (the level the exam is at) are 8.325 notes/problems, Dynamics
of the Standard Model (Donoghue, et al.).

**Useful exam-taking hints:** Don’t be afraid to admit what you don’t know. Don’t try and
talk about things you don’t understand, it will only confuse you and (worse case scenario)
your committee. Try and stay focused on the topic given or the question asked, straying
too far leads to confusion.

**Some Past CTP Part III Topics**

**Some Past CTP Part III Questions**