No Arabic abstract
The evolution equations of the Yukawa couplings and quark mixings are performed for the one-loop renormalisation group equations in six-dimensional models compactified in different possible ways to yield standard four space-time dimensions. Different possibilities for the matter fields are discussed, that is where they are in the bulk or localised to the brane. These two possibilities give rise to quite similar behaviours when studying the evolution of the Yukawa couplings and mass ratios. We find that for both scenarios, valid up to the unification scale, significant corrections are observed.
The evolution equations of the Yukawa couplings and quark mixings are derived for the one-loop renormalization group equations in the two Universal Extra Dimension Models (UED), that is six-dimensional models, compactified in different possible ways to yield standard four space-time dimension. Different possibilities for the matter fields are discussed, such as the case of bulk propagating or localised brane fields. We discuss in both cases the evolution of the Yukawa couplings, the Jarlskog parameter and the CKM matrix elements, and we find that, for both scenarios, as we run up to the unification scale, significant renormalization group corrections are present. We also discuss the results of different observables of the five-dimensional UED model in comparison with these six-dimensional models and the model dependence of the results.
The evolution equations of the Yukawa couplings and quark mixings are derived for the one-loop renormalization group equations in the 5D Minimal Supersymmetric Standard Model on an {$S^1 / Z_2$} orbifold. Different possibilities for the matter fields are discussed such as the cases of bulk propagating or brane localised fields. We discuss in both cases the evolution of the mass ratios and the implications for the mixing angles.
We present a complete set of new flavour-permutation-symmetric mixing observables. We give expressions for these plaquette invariants, both in terms of the mixing matrix elements alone, and in terms of manifestly Jarlskog-invariant functions of fermion mass matrices. While these quantities are unconstrained in the Standard Model, we point out that remarkably, in the case of leptonic mixing, the values of most of them are consistent with zero, corresponding to certain phenomenological symmetries. We give examples of their application to the flavour-symmetric description of both lepton and quark mixings, showing for the first time how to construct explicitly weak-basis invariant constraints on the mass matrices, for a number of phenomenologically valid mixing ansatze.
We consider a five-dimensional Minimal Supersymmetric Standard Model compactified on a S1/Z2 orbifold, and study the evolution of neutrino masses, mixing angles and phases for different values of tan beta and different radii of compactification. We consider the usual four dimensional Minimal Supersymmetric Standard Model limit plus two extra-dimensional scenarios: where all matter superfields can propagate in the bulk, and where they are constrained to the brane. We discuss in both cases the evolution of the mass spectrum, the implications for the mixing angles and the phases. We find that a large variation for the Dirac phase is possible, which makes models predicting maximal leptonic CP violation especially appealing.
We explore a simple parameterization of new physics that results in an ultraviolet complete gauge-quark sector of the Standard Model. Specifically, we add an antiscreening contribution to the beta functions of the gauge couplings and a flavor-independent, antiscreening contribution to the beta functions of the Yukawa couplings. These two free parameters give rise to an intricate web of Renormalization Group fixed points. Their predictive power extends to the flavor structure and mixing patterns, which we investigate to demonstrate that some of the free parameters of the Standard Model could be determined by the Renormalization Group flow.