Related papers: New issues in quark-lepton symmetry
Left--right symmetry breaking in a model with composite Higgs scalars is discussed. It is assumed that the low--energy degrees of freedom are just fermions and gauge bosons and that the Higgs bosons are generated dynamically through a set…
A phenomenological analysis of the three-family local gauge group $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ with right-handed neutrinos is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we…
The low-energy manifestations of a minimal extension of the electroweak standard model based on the quark-lepton symmetry $SU(4)_V \otimes SU(2)_L \otimes G_R$ of the Pati-Salam type are analyzed. Given this symmetry the third type of…
We propose a model of quark and lepton mixing based on the tetrahedral A(4) family symmetry with quark-lepton unification via the tetra-colour Pati-Salam gauge group SU(4)_{PS}, together with SU(2)_L x U(1)_R. The "tetra-model" solves many…
We study low energy implications of F-theory GUT models based on $SU(5)$ extended by a $U(1)'$ symmetry which couples non-universally to the three families of quarks and leptons. This gauge group arises naturally from the maximal…
We propose a supersymmetric SU(5)xSU(5) model, where the quarks and leptons live in a U(1) product group theory space that is compactified on the real projective plane RP^2. The fermion generations are placed on different points in the…
Instead of right-handed neutrino singlets, the standard model is extended to include lepton triplets $(\Sigma^+, \Sigma^0, \Sigma^-)$. Each quark and lepton family may now transform under an anomaly-free $U(1)_X$ gauge symmetry, known…
Four different supersymmetric models based on SU(2)_L X U(1)_R X U(1)_B-L and SU(2)_L X SU(2)_R X U(1)_B-L gauge symmetry groups are studied. U(1)_B-L symmetry is broken spontaneously by a vacuum expectation value (VEV) of a sneutrino…
In this work we study a predictive model based on a partially unified theory possessing the gauge symmetry of the Pati-Salam group, $SU(2)_L\times SU(2)_R\times SU(4)_C$ supplemented by a global Peccei-Quinn symmetry, $U(1)_{PQ}$. A…
It is shown that a chiral SU(2) model can break Lorentz symmetry spontaneously at the Lagrangian level when gauge bosons become massive. This model seems to propose the principles and conceptual foundations leading to a unified picture of…
We explore a possible phase where chiral $SU(2)_L \times SU(2)_R$ symmetry is spontaneously broken while its center $Z_2$ symmetry remains unbroken and its consequence on thermal quantities. In this phase, chiral symmetry breaking is driven…
A $SU(N)_L\times SU(N)_R$ gauge theory for a scalar multiplet $Y$ transforming in the bi-fundamental representation $(N,\bar N)$ preserves, for $N>4$, an accidental $U(1)$ symmetry firstly broken at operator dimension $N$. Two…
In this thesis we study top-condensation models of electroweak symmetry breaking. In particular we investigate a scenario in which the CP symmetry is broken spontaneously due to the same condensates responsible of electroweak symmetry…
We show that a model where both CP and R-parity are spontaneously broken exists. We study the electroweak symmetry breaking sector of the model and find minima consistent with experimentally viable Higgs boson masses. We also demonstrate…
A spontaneously-broken CP provides an alternative to the KM mechanism for CP violation with the advantage that the strong CP problem is solved. We consider, for such a model with a new gauged U(1), the incorporation of low-energy…
The promising solution to the strong CP problem by a Peccei-Quinn (PQ) symmetry may introduce quality and hierarchy problems, which are both relevant to Planck physics. In this paper, we study whether both problems can be explained by…
Solutions of the Strong CP Problem based on the spontaneous breaking of CP must feature a non-generic structure and simultaneously explain a coincidence between a priori unrelated CP-even and CP-odd mass scales. We show that these…
We have investigated some phenomenological aspects of an $SU(2)\times U(1)$ scenario where scalars belonging to arbitrary representations of $SU(2)$ are involved in electroweak symmetry breaking. The resulting interaction terms are derived.…
We study the relation between the scale of chiral symmetry spontaneously breaking and constituent quark mass. We argue that this relation partly reveals strong interaction origination of chiral symmetry breaking. We show that the relation…
In models with spontaneous symmetry breaking by scalar fields in large group representations, we observe that some of the scalar masses can be loop-suppressed with respect to the naive expectation from symmetry selection rules. We present…