Seminarium Teorii Oddziaływań Elementarnych

I discuss the relation between QFT amplitudes calculated in the"interaction" basis and "mass eigenstate" basis, especially importantfor flavor physics. I present and prove a theorem of matrix analysisallowing to algebraically translate an amplitude written in masseigenbasis into flavor mass insertions, without performingdiagrammatic calculations in the interaction basis. I also describeMassToMI Mathematica package automatizing such translation and discussits application to physical examples of neutron Electric Dipole Momentand Higgs boson decays in the MSSM.