is a property of a system or theory where the combined charge conjugation (replacing particles with their anti-particles) and parity (reversing the sign of every vector, equivalent to reflecting the system through the origin) operations yield non-equivalent results. Only the weak interaction is know ...
Amplitudes in QFT are typically real. I'd like to understand the physical meaning of an amplitude having a phase. I know of three ways that amplitudes can get a phase: If the couplings have an ...