Study notes and personal project updateshttps://www.t-duality.com/https://www.t-duality.com/notes/qft/active-and-passive-transformations/https://www.t-duality.com/notes/qft/active-and-passive-transformations/A geometric account of active and passive transformations in quantum field theory, separating spacetime, coordinate maps, and field configurations.Mon, 03 Aug 2026 00:00:00 GMThttps://www.t-duality.com/notes/qft/schwartz-232/https://www.t-duality.com/notes/qft/schwartz-232/Notes and an erratum for Section 2.3.2 of Schwartz.Sun, 26 Apr 2026 00:00:00 GMT