Left–right symmetric model of neutrino dark energy

Abstract

We implemented the neutrino dark energy (νDE) proposal in a left-right symmetric model. Unlike earlier models of mass varying neutrinos, in the present model the mass parameter that depends on the scalar field (acceleron) remains very light naturally. The required neutrino masses then predicts the U (1)R breaking scale to be in the TeV range, providing new signals for LHC. Compared to all other νDE proposals, this model has the added advantage that it can also be embedded into a grand unified theory. In this scenario leptogenesis occurs through decays of scalars at very high energy.Present observations reveal that the dark energy ∼ (3 × 10 −3 eV) 4 [1] contributes about 70% to the total density of our universe. Since the only known physics around this scale is the neutrino mass, there are now attempts to relate the origin of the dark energy with the neutrino masses [2,3,4]. This connection is based on the idea of quintessence [5], and have several interesting consequences [6,7].In the original model of neutrino dark energy (νDE) or the mass varying neutrinos (mavans) [2,3,4], the standard model is extended by including singlet righthanded neutrinos N i , i = 1, 2, 3, and giving a Majorana mass to the neutrinos which varies with a scalar field, the acceleron. This model was not complete and several problems were pointed out [3,8]. Some of the problems have been solved in subsequent works [9,10], but more studies are required to make this model fully consistent. The main motivation of the present article is to justify the very low scale entering in this model naturally, embed this idea into a left-right symmetric model and also in grand unified theories. Since the right-handed neutrinos are not very heavy, leptogenesis occurs through scalar decays.In the νDE models, the Majorana masses of the righthanded neutrinos varies with the acceleron field and that relates the scale of dark energy with the light neutrino masses. Naturalness requires the Majorana masses of the right-handed neutrinos also to be in the range of eV, so the main motivation of the seesaw mechanism is lost. The smallness of the light neutrino masses cannot be attributed to a large lepton number violating mass scale in the theory. In this νDE model, the neutrino Dirac masses cannot be made to vary with the acceleron field, since that will then allow coupling of the acceleron field with the charged leptons and a natural scale for the dark energy will then be the mass of the heaviest charged lepton. For the same reason, this mechanism cannot be embedded into a left-right symmetric model, in which the SU (2) R group relates the right-handed neutrinos to the right-handed charged leptons.The problem with the smallness of the mass parameter that depends on the acceleron field can be softened in the νDE models with triplet Higgs scalars [10]. In these models the standard model is extended to include triplet Higgs scalars. In any phenomenologically consistent triplet Higgs scalar model, lepton number is violated explicitly by a trilinear scalar couplings of ...

Phenomenology of hybrid scenarios of neutrino dark energy

“…For example, different powers of A may appear in the superpotential or the neutrino masses may originate from a different type of seesaw mechanism (e.g. from a so-called double [30] or multiple seesaw) such that n ν m ν ∼ n ν v 2 u /|A| β , and so on. Furthermore, one may anticipate that the parameters α and β in realistic values should be positive integers.…”

“…This implies β = n in equation ( 4). We note that another way to realize higher powers of β would be to generate neutrino masses via a multiple seesaw (see, e.g., [30] for a model of neutrino dark energy using the double seesaw mechanism).…”

Radiative neutrino mass generation and dark energy

“…in [22,23]. Moreover, the Majorana neutrino superfluidity and the stability of the neutrino dark energy have been discussed in [24].…”

“…Some models to explain neutrino masses and dark energy at the TeV scale have been explored in Refs. [22,23]. Moreover, the Majorana neutrino superfluidity and the stability of the neutrino dark energy have been discussed in Ref.…”

Neutrino dark energy and leptogenesis with TeV scale triplets

“…In some scenarios, a direct connection through the formation of a neutrino condensate at a late epoch of the early universe using the effective self-interaction has been explored [1][2][3][4][5][6][7]. Another class of models invoke the variation of neutrino masses to dynamically obtain the dark energy [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. In this work, we will focus on the latter approach.…”