Yukawa Corrections from Four-Point Functions in Intersecting D6-Brane Models

TL;DR

This paper investigates how four-point interactions in intersecting D-brane models can improve the accuracy of Standard Model fermion mass and mixing predictions, addressing discrepancies in charged lepton masses.

Contribution

It demonstrates that including four-point interaction corrections in intersecting D-brane models can yield fermion masses and mixings closer to experimental data.

Findings

Four-point interactions significantly improve fermion mass predictions.

Corrected models better match experimental fermion mass hierarchies.

Potential broader application to other string-inspired models.

Abstract

We discuss corrections to the Yukawa matrices of the Standard Model (SM) fermions in intersecting D-brane models due to four-point interactions. Recently, an intersecting D-brane model has been found where it is possible to obtain correct masses and mixings for all quarks as well as the tau lepton. However, the masses for the first two charged leptons come close to the right values but are not quite correct. Since the electron and muon are quite light, it is likely that there are additional corrections to their masses which cannot be neglected. With this in mind, we consider contributions to the SM fermion mass matrices from four-point interactions. In an explicit model, we show that it is indeed possible to obtain the SM fermion masses and mixings which are a better match to those resulting from experimental data extrapolated at the unification scale when these corrections are included. These corrections may have broader application to other models.