Related papers: Neutrino Masses from the Top Down
String theories in principle address the origin and values of the quark and lepton masses. Perhaps the small values of neutrino masses could be explained generically in string theory even if it is more difficult to calculate individual…
Neutrino oscillations constitute the first experimental confirmation of new physics, as they require a new piece that is absent in the Standard Model, non-zero neutrino masses. Questions such as how these masses are generated or why they…
In this review, the seesaw mechanism for generating the mass of active light neutrinos (both Majorana and Dirac) is considered on the basis of effective field theory. In particular, we review certain models that extend the Standard Model by…
We consider a class of models in which the neutrinos acquire Majorana masses through mixing with singlet neutrinos that emerge as composite states of a strongly coupled hidden sector. In this framework, the light neutrinos are partially…
The existence of neutrino mass and mixing is a strong pointer towards physics beyond the standard model. An overview of the possibility of having neutrino masses in supersymmetric theories is attempted here. Some of the recent works…
We show that Dirac neutrino masses of the right size can arise from the Kahler potential of supergravity. They are proportional to the supersymmetry and the electroweak breaking scales. We find that they have the experimentally observed…
An alternative to the conventional see-saw mechanism is proposed to explain the origin of small neutrino masses in supersymmetric theories. The masses and couplings of the right-handed neutrino field are suppressed by supersymmetry…
Neutrino masses and mixings can be generated in many different ways, with some of these scenarios featuring new physics at energy scales relevant for Large Hadron Collider searches. A systematic approach to constructing a large class of…
The theory that the extra-space component of the gauge field is identified with the standard model Higgs boson, is called the gauge-Higgs unification (GHU) scenario. We examine how the small neutrino masses are naturally generated in the…
We present a new approach for generating tiny neutrino masses. The Dirac neutrino mass matrix gets contributions from two new Higgs doublets with their vevs at the electroweak (EW) scale. Neutrino masses are tiny not because of tiny Yukawa…
Mixing between light and heavy neutrino states has been proposed as an explanation (or partial explanation) for the 3-sigma NuTeV anomaly and the 2-sigma departure of the $Z^0$ invisible width from its expected value. I assume herein that…
A simple mechanism to generate Dirac masses for the neutrinos in SU(5) supersymmetric grand unified theory is proposed. The tiny Dirac masses are induced by the small mixing between the Higgs fields and another superheavy fields. The mixing…
Recently it was proposed that the standard model (SM) degrees of freedom reside on a $(3+1)$-dimensional wall or ``3-brane'' embedded in a higher-dimensional spacetime. Furthermore, in this picture it is possible for the fundamental Planck…
We consider the seesaw mechanism of neutrino mass generation in the light of our present knowledge of the neutrino masses and mixing. We analyse the seesaw mechanism constrained by the following assumptions: (1) minimal seesaw with no Higgs…
We present a model of neutrino masses combining the seesaw mechanism and strong Dirac mass hierarchy and at the same time exhibiting a significantly reduced hierarchy at the level of active neutrino masses. The heavy Majorana masses are…
We discuss models of neutrino masses that lead to a large mixing angle for atmospheric neutrino oscillations. In particular we study a mechanism where a simple texture for the Dirac matrix leads to the observed pattern of mixings for a…
In theories with a low quantum gravity scale, global symmetries are expected to be violated, inducing excessive proton decay or large Majorana neutrino masses. The simplest cure is to impose discrete gauge symmetries, which in turn make…
A plausible explanation for the lightness of neutrino masses is that neutrinos are massless at tree level, with their mass (typically Majorana) being generated radiatively at one or more loops. The new couplings, together with the…
The most plausible see-saw explanation of the smallness of the neutrino masses is based on the assumption that total lepton number is violated at a large scale and neutrinos with definite masses are Majorana particles. In this review we…
The scale of neutrino mass generation may be too large to explore directly, but useful information may still be extracted from independent experimental channels. Here I survey various model independent probes of Majorana neutrino mass…