Muon-Tau Symmetry and Leptogenesis in the Minimal Seesaw Model

The measured values for the mixture angles in neutrino oscillations suggest the existence of a symmetry of interchange of flavor between muon and tau neutrinos. Using this symmetry we analyzed the minimal seesaw model for neutrino masses, where the Majorana mass was diagonalized, and it is demonstrated that the model supports at most 3 CP violation phases and 5 real masses at high energies. Nevertheless, at low energies, only 4 parameters of mass and one relative Majorana CP phase remain. Therefore using the experimental values of the masses square differences, the mixture angles and the hierarchy, we can determine some parameters of the model but not all. Also we propose the use of the parameter of baryonic asymmetry of the universe due to leptogenesis to determine one more phase of the model. Finally we used a normal hierarchy for the masses of the right handed neutrinos to make an approximation, that allowed us to completely reconstruct the mass matrix for left handed neutrinos. In special the value of mee is determined which can be compared with the results of the neutrinoless double decay beta.Comment: This is a thesis written to obtain a Master in Science degree, made under the advise of Abdel Perez Lorenzana, Ph

Probing Lepton Flavor Triality with Higgs Boson Decay

If neutrino tribimaximal mixing is explained by a non-Abelian discrete symmetry such as $A_4$, $T_7$, $\Delta(27)$, etc., the charged-lepton Higgs sector has a $Z_3$ residual symmetry (lepton flavor triality), which may be observed directly in the decay chain $H^0 \to \psi_2^0 \bar\psi_2^0$, then $\psi_2^0 (\bar\psi_2^0) \to l_i^+ l_j^- ~(i \neq j)$, where $H^0$ is a standard-model-like Higgs boson and $\psi_2^0$ is a scalar particle needed for realizing the original discrete symmetry. If kinematically allowed, this unusual and easily detectable decay is observable at the LHC with 1 fb$^{-1}$ for E_{cm} = 7 TeV.Comment: PRD versio

Quasidegeneracy of Majorana Neutrinos and the Origin of Large Leptonic Mixing

We propose that the observed large leptonic mixing may just reflect a quasidegeneracy of three Majorana neutrinos. The limit of exact degeneracy of Majorana neutrinos is not trivial, as leptonic mixing and even CP violation may occur. We conjecture that the smallness of $|U_{13}|$, when compared to the other elements of $U_{PMNS}$, may just reflect the fact that, in the limit of exact mass degeneracy, the leptonic mixing matrix necessarily has a vanishing element. We show that the lifting of the mass degeneracy can lead to the measured value of $|U_{13}|$ while at the same time accommodating the observed solar and atmospheric mixing angles. In the scenario we consider for the breaking of the mass degeneracy there is only one CP violating phase, already present in the limit of exact degeneracy, which upon the lifting of the degeneracy generates both Majorana and Dirac-type CP violation in the leptonic sector. We analyse some of the correlations among physical observables and point out that in most of the cases considered, the implied strength of leptonic Dirac-type CP violation is large enough to be detected in the next round of experiments.Comment: 16 pages, 4 figures. Matches published version, references added, improved discussion, results unchange

KettleBell Ultra

This project will consist of an attachment to an average kettlebell that will track the number of repetitions that the user has performed. The device will send this data over Bluetooth to a smart phone application so the user can track their workout accurately

Dark Vector-Gauge-Boson Model

A model based on SU(3)_C X SU(2)_L X U(1)_Y X SU(2)_N has recently been proposed, where the SU(2)_N vector gauge bosons are neutral, so that a vector dark-matter candidate is possible and constrained by data to be less than about 1 TeV. We explore further implications of this model, including a detailed study of its Higgs sector. We improve on its dark-matter phenomenology, as well as its discovery reach at the LHC (Large Hadron Collider).Comment: 15 pages, 4 figure

Quantum Computers and Quantum Coherence

If the states of spins in solids can be created, manipulated, and measured at the single-quantum level, an entirely new form of information processing, quantum computing, will be possible. We first give an overview of quantum information processing, showing that the famous Shor speedup of integer factoring is just one of a host of important applications for qubits, including cryptography, counterfeit protection, channel capacity enhancement, distributed computing, and others. We review our proposed spin-quantum dot architecture for a quantum computer, and we indicate a variety of first generation materials, optical, and electrical measurements which should be considered. We analyze the efficiency of a two-dot device as a transmitter of quantum information via the ballistic propagation of carriers in a Fermi sea.Comment: 13 pages, latex, one eps figure. Prepared for special issue of J. Mag. Magn. Matl., "Magnetism beyond 2000". Version 2: small revisions and correction

A global database for metacommunity ecology, integrating species, traits, environment and space

The use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. Although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across ecosystems, taxa and spatial scales. To address this gap, we collated 80 datasets from trait-based studies into a global database for metaCommunity Ecology: Species, Traits, Environment and Space; “CESTES”. Each dataset includes four matrices: species community abundances or presences/absences across multiple sites, species trait information, environmental variables and spatial coordinates of the sampling sites. The CESTES database is a live database: it will be maintained and expanded in the future as new datasets become available. By its harmonized structure, and the diversity of ecosystem types, taxonomic groups, and spatial scales it covers, the CESTES database provides an important opportunity for synthetic trait-based research in community ecology

Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead.

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology