Yukawa couplings in string theory: the case for F-theory GUT's

14th Mexican Workshop on Particles and Fields

Font, Anamaría^1

Departamento de Física, Centro de Física Teórica y Computacional, Facultad de Ciencias, Universidad Central de Venezuela, A.P. 20513, Caracas

1020-A, Venezuela^1

关键词: Hierarchical structures;    Instantons;    Physical coupling;    Second generation;    Symmetry-breaking;    The standard model;    Yukawa couplings;    Yukawa matrices;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/651/1/012009/pdf
DOI  :  10.1088/1742-6596/651/1/012009

来源: IOP

【 摘 要 】

We study the pattern of Yukawa couplings in local F-theory SU(5) GUT's. Couplings for the third family of quarks and leptons appear at the perturbative level, but to reproduce the observed couplings for the lighter families requires non-perturbative dynamics. We show that corrections due to instanton effects do lead to a Yukawa matrix with a hierarchical structure. Our results apply to both down-like 10 × 5 × 5 and up- like 10 × 10 × 5 couplings. The models include magnetic fluxes needed for a chiral spectrum and for symmetry breaking down to the Standard Model. We compute the holomorphic couplings via residues and then obtain the physical couplings taking into account the normalization of wavefunction profiles. Combining non-perturbative corrections and magnetic fluxes allows to fit the measured masses and hierarchies of the third and second generations in the Standard Model.