Evaluation of the two lightest quark masses

Simple relations between the masses of the two lightest up and down quarks were obtained on the basis of the simple physically based model compatible with the present-day theory of strong interactions, i.e. with quantum chromodynamics. Relations between the u and d quark masses, on one hand, and nucleon and pion masses, on the other hand, are also established. Thus, the obtained in such a way elementary formula mu/md = 1/(1+√2), relating u and d quark masses, appears to be in excellent agreement with a number of theoretical calculations of the ratio mu/md of the lightest quark masses. The u and d quark masses mu = 1.903 MeV, md = 4.594 MeV, calculated with the help of the obtained relations, are also in very good agreement with the modern evaluations and calculations of these quantities. The average of the u and d quark masses m̅ud = ΔMπ/√2 ≅ 3.248 MeV, obtained in the proposed approach, is in good agreement with previous calculations too.