PHY 7669 "Quantum Field Theory II"
Class Diary for Spring 2013

 

Date Notes
Monday 1/7 Introductions, course policies. Review of final exam.
Wednesday 1/9 Phi cubed in 6 dimensions. Extra dimensions: Kaluza-Klein theories.
Friday 1/11 Complex scalar field in 5 dimensions. Kaluza-Klein tower.
Monday 1/14 Invariant mass distributions, bump hunting for resonances, narrow width approximation. Angular distributions and spin. Energy dependence of the production cross-section near threshold and spin.
Wednesday 1/16 Section 7.1 Field Strength Renormalization. Bare parameters. Physical mass. Field-strength renormalization constant. The electron propagator: resumming the 1PI diagrams to all orders. Relation between the bare and physical parameters.
Friday 1/18 The electron self energy at one loop.
Monday 1/21 Martin Luther King Jr. Day
Wednesday 1/23 LSZ reduction formula. Relation between matrix elements and Feynman diagrams. Justification for the subtraction procedure for the F1 form factor.
Friday 1/25 Sec. 7.3: The optical theorem. Unstable particles.
Monday 1/28 Sec. 7.4: The Ward-Takahashi identity.
Wednesday 1/30 Finish section 7.4: application of the Ward-Takahashi identity. Begin 7.5: Renormalization of the electric charge. Tensor structure of the photon propagator.
Friday 2/1 Resummation of 1PI diagrams into the photon proipagator. Begin chapter 10: Counting of UV divergences. Superficial degree of divergence. Algebraic relations between the number of loops, vertices, electron and photon lines in a QED diagram.
Monday 2/4 Formula for the superficial degree of divergence of a QED diagram in terms of the number of external photon and fermion lines. Classification of the potentially divergent diagrams in QED.
Wednesday 2/6 Generalization to QED in d dimensions. Renormalizable, super-reormalizable and non-renormalizable theories. Another example: phiN theory.
Friday 2/8 Relation between renormalizability and the dimension of the coupling constants. Renormalized perturbation theory. Bare and renormalized quantities. Counterterms. Feynman rules.
Monday 2/11 One-loop structure of phi4 theory. Renormalization of the 4-point function. Dimensional regularization (section 7.5).
Wednesday 2/13 Renormalization of the 2-point function. Mass and wave-function renormalization.
Friday 2/15 Renormalization at higher orders.
Monday 2/18 Dark matter. Boltzmann equation.
Wednesday 2/20 Continue with the solution to the Boltzmann equation.
Friday 2/22 Finish the derivation of the DM relic density.
Monday 2/25 The Callan-Symanzik equation.
Wednesday 2/27 Solution to the Callan-Symanzik equation.
Friday 3/1 RGE for the scalar self-coupling in lambda phi4 theory. Solution to the RGE. Landau pole. Triviality bounds on the Higgs mass.
Monday 3/4 Spring break.
Wednesday 3/6 Spring break.
Friday 3/8 Spring break.
Monday 3/11 Mass-independent renormalization schemes, minimal subtraction. Physical mass versus running mass. Alternative derivation of the RGEs.
Wednesday 3/13 Discussion on final projects.
Friday 3/15 Path integrals. Discretization.
Monday 3/18 Finish the proof that the path inegral amplitude satisfies the Schrodinger equation. Discussion of Homework No. 3.
Wednesday 3/20 Difference between Hamiltonian and Lagrangian description. Generalization to arbitrary systems. Integration over the momenta in the path integral.
Friday 3/22 Generating functional for the free scalar field theory.
Monday 3/25 Grassmann calculus. Grassmann integrals. Functional quantization of fermions.
Wednesday 3/27 Non-abelian gauge theories. Covariant derivative. Transformation law of the gauge field. Field strength tensor.
Friday 3/29 Transformation law of the field-strength tensor. Gauge invariant Lagrangians.
Monday 4/1 Basic facts about Lie algebras. Fndamental and adjoint representations of SU(N).
Wednesday 4/3 Non-abelian gauge theories: application. The Standard Model. Particle representations of the SM. Gauge couplings of fermions.
Friday 4/5 Triple and quartic gauge boson couplings. The beta functions of the SM. Running of the strong coupling constant. Asymptotic freedom. Gauge coupling unification. Yukawa couplings in the Standard Model.
Monday 4/8 The Effective Potential. Section 11.3. The Effective Action. Section 11.4. Computation of the Effective Action.
Wednesday 4/10 QCD-I. Section 17.1. From Quarks to QCD. Section 17.2. Electron-positron annihilation into Hadrons. (Avoid references to results from Final Project of Part I.) Section 17.3. Deep Inelastic Scattering. The Parton Distribution Functions.
Friday 4/12 QCD-II. Section 17.4. Hard Scattering Processes in Hadron Collisions.
Monday 4/15 The Higgs Mechanism. Section 11.1. Spontaneous Symmetry Breaking. Goldstone's theorem. Section 20.1. The Higgs mechanism. (Skip the SU(3) example in the "Non-Abelian Examples" subsection, as well as the "Formal Description of the Higgs Mechanism" subsection.)
Wednesday 4/17 No class: KM out of town.
Friday 4/19 No class: KM out of town.
Monday 4/22 Electroweak Theory. Section 20.2. The Glashow-Weinberg-Salam Theory of Weak Interactions. (Skip "Anomaly Cancellation" and "A Higgs Sector?".)
Wednesday 4/24 Beyond the Standard Model. Section 22.2. Grand Unification and its Paradoxes. Section 22.4. Supersymmetry. MSSM. Superpartners. Fermionic superpartner spectrum: higgsinos and gauginos versus neutralinos and charginos. Interactions of the superpartners. Section 22.5. Toward the Ultimate Theory of Nature.