Matter-antimatter asymmetry – CP violation in strong and weak interactions

The aim of this work is the theoretical description of CP violation phenomena in strong and weak interactions. For weak interactions, we will see the occasions when CP violations were observed and how this is predicted by the Standard Model, according to the CKM matrix. In the case of strong interactions, it is described how the vacuum structure in QCD, necessary to solve the problem $U{(1)}_A$, predicts the presence of a term proportional to $\theta$ that violates CP. To agree with the experimental limits this parameter must be small ($\theta \le {10}^{-10}$). The focus is on the chiral solution proposed by Peccei and Quinn, which is related to a light pseudoscalar particle, the axion.

Keywords
Matter-antimatter asymmetry; CP violation