2 papers
hep-ph2025
Unstable Particles in Quantum Field Theory
Scott Willenbrock
In honor of Dave Roper's 90th birthday, I present a pedagogical introduction to our modern understanding of unstable particles in Quantum Field Theory, based on the analytic struct…
hep-ph2025
A Brief History of Mass
Scott Willenbrock
It has been known since the 1950's that an unstable particle is associated with a complex pole in the propagator. This had to be rediscovered twice: in the early 1970's in the cont…