Teaching

Harvard University

Fall 2026

Teaching Fellow, Physics 253a: Quantum Field Theory I

Instructor: Matthew Reece. I run the weekly recitation sections and office hours, help write and grade the problem sets and exams, and handle course communications.

Daria Trotsenko at the blackboard during a QFT section — At the blackboard during section, fall 2026.

Section notes

Handouts I wrote for the sections, roughly following Srednicki and Schwartz. They are informal and may contain typos; corrections are welcome by email.

Section 1 — Lorentz invariance (September 9)
Section 2 — Contour integration and path integrals (September 16)
Section 3 — Gaussian integrals (September 23)
Section 4 — Recap and symmetries (September 30)
Section 5 — Feynman diagrams in position space (October 7)
Section 6 — LSZ, Feynman rules in momentum space, cross sections and decay rates (October 14)
Section 7 — Regularization and renormalization (October 21)
Section 8 — Groups, representations, and Lorentz transformations (October 28)
Section 9 — The Lagrangian for spin-½ fields (November 4)