Agenda
Histórico

25 de agosto de 2025
14h00
Anfiteatro Verde (IFSC-USP)

Gero von Gersdorff
Departamento de Física
Pontifícia Universidade Católica do Rio de Janeiro

Inequalities for Standard Model Yukawa Couplings

The masses of the Standard Model (SM) matter fields, as well as their coupling to the W boson, satisfy a very curious hierarchical structure that has inspired countless "flavor models". In the SM, this structure is encoded in the so-called Yukawa matrices, three by three complex matrices describing the coupling of the matter fields to the Higgs boson. We show that these matrices satisfy a set of simple yet nontrivial inequalities. The relations we derive are independent of the basis used to define the SM matter fields, and, amongst other things, place strong constraints on the alignment of the columns of the up-type and down-type Yukawa matrices, as well as their cofactor matrices. The reason why one can obtain such strong statements can be traced back to the hierarchical nature of the fermion masses and quark mixings themselves. The inequalities should be seen as very strong necessary conditions on the Standard Model Yukawa couplings and thus are useful for constraining flavor models.