<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>C</mml:mi><mml:mi>P</mml:mi></mml:math> asymmetries and higher-order unitarity relations

The main focus of this paper is to introduce a new method control perturbative calculations CP asymmetric reaction rates in the Boltzmann equation. asymmetries particle reactions are traditionally calculated terms complex couplings, Feynman integrals, and Cutkosky rules. We use an expansion $S$-matrix unitarity condition instead, obtaining general expression for without reference imaginary part loops. Asymmetry cancelations implied by CPT manifested diagrammatic way easy track at any order perturbation theory. demonstrate power framework within right-handed neutrino top-quark scattering seesaw type-I leptogenesis.