Video for my thesis dissertation
This is one of the videos I used for my PhD dissertation. The pole position is localized, for each value of "a" and "b", by using complex numerical integration and the Cauchy's theorem (see App.D of [PRD91, 075017]).
The numerical integrand, the unitarization methods and the perturbative scattering amplitudes are coded in FORTRAN. The integration itself (once parametrized to 1-real variable integrations), is done via SciPy library (and f2py to link FORTRAN and Python). For the animation, I use matplotlib and multiprocessing.