8.851 | Spring 2013 | Graduate

Effective Field Theory

Calendar

LEC # TOPICS SUBTOPICS
Part I: Effective Field Theory (EFT)
1 Introduction to Effective Field Theory (EFT) EFT of Hydrogen, top-down and bottom-up, renormalizable EFT
2 Dimensional Power Counting Marginal & (ir)relevant operators, Standard Model as and EFT, start field redefinitions
3 Field Redefinitions Finish field redefinitions, discuss loops, regularization and the impact on power counting
4 Matching and Decoupling Alphas(mu) and integrating out massive particles in MSbar, Electroweak Hamiltonian Hw
5 Classic Operator Renormalization Group Equations (RGE) Renormalization group equations for Hw, running & scale variations, LL, NLL, …, matching and scheme dependence
6 Chiral Lagrangians Linear sigma model & field redefinitions, non-linear Lagrangian & symmetry breaking, Spurion analysis, start loops
7 Chiral Loops Loops in ChPT in dimensional regularization, naive dimensional analysis, momentum power counting theorem, SU3, start Heavy Quark Effective theory 
8 Heavy Quark Effective Theory (HQET) QCD to HQET, velocity labels, power counting, heavy quark symmetry, spectroscopy, covariant superfields, start loops
9 HQET Matching & Power Corrections Detailed matching calculation, velocity dependent anomalous dimension and Wilson coefficients, power corrections and reparameterization invariance
10 HQET Examples Heavy hadron masses, exclusive semileptonic decays, inclusive decays and OPE, pole mass versus short distance masses, start renormalons
11 Renormalons Bubble sum for heavy quark mass, removing renormalon ambiguities with scale R, R-RGE, all orders formula for Lambda_QCD
12 More Renormalons Solution of R-RGE, sum rule for renormalons, renormalons in OPEs, connecting Wilsonian and Continuum EFT
13 EFT with Fine Tuning 2-nucleon nonrelativisitic EFT, bubble sums & effective range expansion, fine tuning from RGE flow between fixed pts, power corrections
14 EFT with Fine Tuning Part 2 Conformal invariance, SU(4) symmetry, calculations with the deuteron bound state, start SCET
Part II: Soft-Collinear Effective Theory (SCET)
15 Soft-Collinear Effective Theory (SCET) Introduction Degrees of freedom, light cone coordinates, SCETI & SCETII, jets and energetic hadrons, collinear propagators
16 SCET Collinear Wilson Lines W from integrating out offshell propagators, SCET Lagrangian
17 SCET Multipole Expansion Multipole expansion with label and residual momenta, label operators, Wilson line identities
18 SCET Beyond Tree Level Gauge symmetry, reparameterization invariance
19 SCET Beyond Tree Level 2 Extension to multiple collinear directions, ultrasoft-collinear factorization via field redefinitions
20 SCET Wilson Coefficients Hard-collinear factorization, quark and gluon building blocks for operators, loops and IR divergences, 0-bin
21 SCET Sudakov Logarithms LL RGE for Sudakov summation, cusp anomalous dimension, convolutions in RGE, start DIS factorization
22 SCET for DIS Finish DIS factorization, 1-loop renormalization of PDFs, convolutions in other processes
23 SCET for Dijets e+e- to dijets, factorize cross section with measurements, jet function, hemisphere soft function, peak/tail/fixed order regions, all orders RGE
24 SCETII Soft-collinear factorization, SCETI to SCETII matching, power counting theorems, γ*γ -> π0 example
25 SCETII Rapidity RGE B->Dπ example, rapidity divergences, massive sudakov form factor, rapidity RGE
26 SCET for LHC Higgs pT distribution, Inclusive Drell-Yan, Threshold Drell-Yan, and Beam Thrust Drell-Yan

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