Related papers: One-Loop Electron Mass and Three-Loop Dirac Neutri…
We discuss a radiative type-I seesaw. In these models, the radiative generation of Dirac neutrino masses allows to explain the smallness of the observed neutrino mass scale for rather light right-handed neutrino masses in a type-I seesaw.…
We study the possibility of generating tiny Dirac masses of neutrinos in Left-Right Symmetric Model (LRSM) without requiring the existence of any additional symmetries. The charged fermions acquire masses through a universal seesaw…
We propose a new mechanism where both Dirac masses for the charged-leptons and Majorana masses for neutrinos are generated via quantum levels. The charged-lepton masses are given by the vacuum expectation values (VEVs) of the Higgs doublet…
A minimal extension of the Standard Model is proposed, where the observed left-handed neutrinos obtain naturally small Majorana masses from a one-loop radiative seesaw mechanism. This model has two candidates (one bosonic and one fermionic)…
We propose a model where the masses of the active neutrinos and a dark matter candidate are generated radiatively through the $U(1)_{B-L}$ gauge symmetry breaking. It is realized by a non-universal $U(1)_{B-L}$ charge assignment on the…
We carry out a systematic investigation for the minimal Dirac neutrino mass models emerging from generic one-loop and two-loop topologies that arise from $d=5$ effective operator with a singlet scalar, $\sigma$. To ensure that the…
The standard model of quarks and leptons is extended to include the gauge symmetry $U(1)_\chi$ which comes from $SO(10) \to SU(5) \times U(1)_\chi$. The radiative generation of Dirac neutrino masses through dark matter is discussed in two…
If three right-handed neutrinos are added to the Standard Model, then, for the three known generations, there are six quarks and six leptons. It is then natural to assume that the symmetry considerations that have been applied to the quark…
The E_6/U(1)_N gauge extension of the Supersymmetric Standard Model, first proposed by Ma, is shown to have exactly the requisite ingredients to realize the important new idea that dark matter is the origin of neutrino mass. With the…
We extend the scalar sector of the neutrinophilic two Higgs doublet model, where small masses of Dirac neutrinos are obtained via a small vacuum expectation value v_nu of the neutrinophilic SU(2)_L-doublet scalar field which has a Yukawa…
If neutrinos are truly Dirac fermions, the smallness of their masses may still be natural if certain symmetries exist beyond those of the standard model of quarks and leptons. We perform a systematic study of how this may occur at tree…
We propose a simple extension to the Standard Model, wherein neutrinos naturally attain small Majorana masses through a one-loop radiative mechanism featuring particles within the loops characterized by milli-charges. Unlike the…
We investigate a simple model of neutrino mass based on SU(3)_C X SU(3)_L X U(1)_X gauge unification. The Yukawa coupling of the model has automatic lepton-number symmetry which is broken only by the self-couplings of the Higgs boson. At…
In the theory of the Dirac equation and in the standard model, the neutrino is massless. Both these theories use Lorentz invariance. In modern approaches however, spacetime is no longer smooth, and this modifies special relativity. We show…
We propose a model in which the origin of neutrino mass is dependent on the existence of dark matter. Neutrinos acquire mass at the three-loop level and the dark matter is the neutral component of a fermion triplet. We show that…
We consider the Peccei-Quinn (PQ) mechanism as the one behind the Dirac neutrino masses when these are generated through the $d=5$ effective operator $\bar{L}\tilde{H}N_R\phi$ at one loop level, with $\phi$ being a Standard Model singlet…
Choosing how gauge $U(1)_\chi$ breaks in the context of $SO(10) \to SU(5) \times U(1)_\chi$, $Z_4$ lepton number may be obtained which maintains neutrinos as Dirac fermions. Choosing $\Delta(27)$ as the family symmetry of leptons,…
We study the gauged U(1)_{B-L} extensions of the models for neutrino masses and dark matter. In this class of models, tiny neutrino masses are radiatively induced through the loop diagrams, while the origin of the dark matter stability is…
We present a scenario of neutrino masses and mixing angles. Each generation includes a sterile right handed neutrino in addition to the usual left handed one. We assume a hierarchy in their Dirac masses similar to, but much larger than the…
We study a class of three-loop models for neutrino mass in which dark matter plays a key role in enabling the mass diagram. The simplest models in this class have Majorana dark matter and include the proposal of Krauss, Nasri and Trodden;…