相关论文: Anarchy and Hierarchy

The masses of the charged fermion and the mixing angles among quarks are observed to be strongly hierarchical, while analogous parameters in the neutrino sector appear to be structure-less or anarchical. We develop a class of unified models…

"Anarchy" is the hypothesis that there is no fundamental distinction among the three flavors of neutrinos. It describes the mixing angles as random variables, drawn from well defined probability distributions dictated by the group Haar…

We study the neutrino mass matrix in supersymmetric models in which the quark and charged lepton mass hierarchies and also the suppression of baryon or lepton number violating couplings are all explained by horizontal $U(1)_X$ symmetry. It…

The neutrino sector of a seesaw-extended Standard Model is investigated under the anarchy hypothesis. The previously derived probability density functions for neutrino masses and mixings, which characterize the type I-III seesaw ensemble of…

We present a quantitative study of the ability of models with different levels of hierarchy to reproduce the solar neutrino solutions, in particular the LA solution. As a flexible testing ground we consider models based on SU(5)xU(1)_F. In…

In the presence of independent generations of leptons, I show that the same type of ambiguity in the mass spectrum arises as was discussed in ref.[1] for neutral kaons. It results from the freedom to add to their Majorana mass matrix,…

Neutrino mixing anarchy is the hypothesis that the leptonic mixing matrix can be described as the result of a random draw from an unbiased distribution of unitary three-by-three matrices. In light of the recent very strong evidence for a…

The combined requirements, of (i) a natural solution to the fermion mass hierarchy problem and (ii) an explanation of both the atmospheric and solar neutrino problems, lead to an essentially unique picture of neutrino masses and mixing…

The charged fermion masses of the three generations exhibit the two strong hierarchies m_3 >> m_2 >> m_1. We assume that also neutrino masses satisfy m_{nu 3} > m_{nu 2} > m_{nu 1} and derive the consequences of the hierarchical spectra on…

The fermion mass problem is briefly reviewed. The observed hierarchy of quark and charged lepton masses strongly suggests the existence of an approximately conserved chiral flavour symmetry beyond the Standard Model. It is argued that in…

Recent neutrino experiments have made very significant progresses and our knowledge of neutrino masses and mixing has considerably improved. In a model independent Monte Carlo approach, we have examined a very large class of textures, in…

The only experimentally observed phenomenon that lies outside the standard model of the electroweak interaction is neutrino oscillations. A way to try to unify the extensive neutrino oscillation data is to add a phenomenological mass term…

Based on existing data, we argue for a peculiar structure of the neutrino mass matrix, that has a block of relatively large elements--a dominant block. We analyze this ansatz and extract its predictions, assuming that the O(1) coefficients…

A non-supersymmetric grand unified theory can exhibit a "radiative fermion mass hierarchy", in which the heavier quarks and leptons get mass at tree level and the lighter ones get mass from loop diagrams. Recently the first predictive model…

Extensions of the Standard Model with additional U(1) symmetries can describe the hierarchy of fermion masses and mixing angles, including neutrinos. The neutrino masses and mixings are determined up to a discrete ambiguity corresponding to…

We update a five-dimensional SO(10) grand unified model of fermion masses and mixing angles originally proposed by Kitano and Li. In our setup Yukawa couplings are anarchical and quark and lepton sectors are diversified by the profiles of…

We revisit the proposal of Craig and Sutherland that Anderson localization in a disordered fermion theory space can generate small neutrino masses from TeV scale physics \citecraig2018exponential}. Building on this idea, we ask a broader…

I attempt to quantify how far from maximal one should expect the atmospheric mixing angle to be given a neutrino mass-matrix that leads, at zeroth order, to a nu_3 mass-eigenstate that is 0% nu_e, 50% nu_mu, and 50% nu_tau. This is done by…

We discuss the possibility of flavor symmetries to explain the pattern of charged lepton and neutrino masses and mixing angles. We emphasize what are the obstacles for the generation of an almost maximal atmospheric mixing and what are the…

If the connection between the fundamental theory and neutrino mass matrices M_\nu is sufficiently complicated all traces of underlying symmetries might be erased and an 'anarchical' M_\nu, with random entries, can arise. It has been claimed…