121 research outputs found
Common Origin of Soft mu-tau and CP Breaking in Neutrino Seesaw and the Origin of Matter
Neutrino oscillation data strongly support mu-tau symmetry as a good
approximate flavor symmetry of the neutrino sector, which has to appear in any
viable theory for neutrino mass-generation. The mu-tau breaking is not only
small, but also the source of Dirac CP-violation. We conjecture that both
discrete mu-tau and CP symmetries are fundamental symmetries of the seesaw
Lagrangian (respected by interaction terms), and they are only softly broken,
arising from a common origin via a unique dimension-3 Majorana mass-term of the
heavy right-handed neutrinos. From this conceptually attractive and simple
construction, we can predict the soft mu-tau breaking at low energies, leading
to quantitative correlations between the apparently two small deviations
\theta_{23} - 45^o and \theta_{13} - 0^o. This nontrivially connects the
on-going measurements of mixing angle \theta_{23} with the upcoming
experimental probes of \theta_{13}. We find that any deviation of \theta_{23} -
45^o must put a lower limit on \theta_{13}. Furthermore, we deduce the low
energy Dirac and Majorana CP violations from a common soft-breaking phase
associated with mu-tau breaking in the neutrino seesaw. Finally, from the soft
CP breaking in neutrino seesaw we derive the cosmological CP violation for the
baryon asymmetry via leptogenesis. We fully reconstruct the leptogenesis
CP-asymmetry from the low energy Dirac CP phase and establish a direct link
between the cosmological CP-violation and the low energy Jarlskog invariant. We
predict new lower and upper bounds on the \theta_{13} mixing angle, 1^o <
\theta_{13} < 6^o. In addition, we reveal a new hidden symmetry that dictates
the solar mixing angle \theta_12 by its group-parameter, and includes the
conventional tri-bimaximal mixing as a special case, allowing deviations from
it.Comment: 60pp, JCAP in Press, v2: only minor stylistic refinements (added Daya
Bay's future sensitivity in Figs.2+8, shortened some eqs, added new
Appendix-A and some references), comments are welcome
Marginal Syllabus
Curatorial note from Digital Pedagogy in the Humanities: Digital annotation can expand our understanding of what is possible when we read together. The social annotation tool Hypothesis facilitates the act of shared reading. It leverages group annotation to enable sentence-level critique and multimodal note-taking on any text found on the Internet. An example of the networked use of this tool comes from Marginal Syllabus, which hosts monthly “annotatathons” on preselected articles. The 2017–18 Syllabus was co-organized with the National Writing Project. Students can participate in any of the scheduled annotatathons and experience networked learning in action, discussing articles with other students and educators globally. The Marginal Syllabus is a multistakeholder collaboration between Hypothesis, a nonprofit organization building an open platform for discussion on the Web; Aurora Public Schools in Aurora, Colorado; and researchers and teacher educators from the University of Colorado Denver School of Education and Human Development in Denver, Colorado
Facilitating the First Move: Exploring Inspirational Design Patterns for Aiding Initiation of Social Encounters
Crowdsourcing hypothesis tests: making transparent how design choices shape research results
To what extent are research results influenced by subjective decisions that scientists make as they design studies? Fifteen research teams independently designed studies to answer five original research questions related to moral judgments, negotiations, and implicit cognition. Participants from 2 separate large samples (total N > 15,000) were then randomly assigned to complete 1 version of each study. Effect sizes varied dramatically across different sets of materials designed to test the same hypothesis: Materials from different teams rendered statistically significant effects in opposite directions for 4 of 5 hypotheses, with the narrowest range in estimates being d = -0.37 to + 0.26. Meta-analysis and a Bayesian perspective on the results revealed overall support for 2 hypotheses and a lack of support for 3 hypotheses. Overall, practically none of the variability in effect sizes was attributable to the skill of the research team in designing materials, whereas considerable variability was attributable to the hypothesis being tested. In a forecasting survey, predictions of other scientists were significantly correlated with study results, both across and within hypotheses. Crowdsourced testing of research hypotheses helps reveal the true consistency of empirical support for a scientific claim.info:eu-repo/semantics/submittedVersio
Minimal Flavour Violation Waiting for Precise Measurements of Delta M_s, S_{psi phi}, A^s_SL, |V_ub|, gamma and B^0_{s,d} -> mu+ mu-
We emphasize that the recent measurements of the B^0_s - bar B^0_s mass
difference Delta M_s by the CDF and D0 collaborations offer an important model
independent test of minimal flavour violation (MFV). The improved measurements
of the angle gamma in the unitarity triangle and of |V_ub| from tree level
decays, combined with future accurate measurements of Delta M_s, S_{psi K_S},
S_{psi phi}, Br(B_{d,s} -> mu+ mu-), Br(B -> X_{d,s} nu bar nu), Br(K+ -> pi+
nu bar nu) and Br(K_L -> pi^0 nu bar nu) and improved values of the relevant
non-perturbative parameters, will allow to test the MFV hypothesis in a model
independent manner to a high accuracy. In particular, the difference between
the reference unitarity triangle obtained from tree level processes and the
universal unitarity triangle (UUT) in MFV models would signal either new
flavour violating interactions and/or new local operators that are suppressed
in MFV models with low tan(beta), with the former best tested through S_{psi
phi} and K_L -> pi^0 nu bar nu. A brief discussion of non-MFV scenarios is also
given. In this context we identify in the recent literature a relative sign
error between Standard Model and new physics contributions to S_{psi phi}, that
has an impact on the correlation between S_{psi phi} and A^s_SL. We point out
that the ratios S_{psi phi}/A^s_SL and (Delta M_s)/(Delta Gamma_s) will allow
to determine (Delta M_s)/(Delta M_s)^SM. Similar proposals for the
determination of (Delta M_d)/(Delta M_d)^SM are also given.Comment: 22 pages, 8 figures, 1 table. Extended discussion of the correlation
between S_{psi phi} and A^s_SL and new proposals to determine Delta
M_q/(Delta M_q)^SM from future measurements, with respect to the first
version. Minor changes and few references adde
The TRPM2 channel nexus from oxidative damage to Alzheimer’s pathologies: An emerging novel intervention target for age-related dementia
Alzheimer’s disease (AD), an age-related neurodegenerative condition, is the most common cause of dementia among the elder people, but currently there is no treatment. A number of putative pathogenic events, particularly amyloid β peptide (Aβ) accumulation, are believed to be early triggers that initiate AD. However, thus far targeting Aβ generation/aggregation as the mainstay strategy of drug development has not led to effective AD-modifying therapeutics. Oxidative damage is a conspicuous feature of AD, but this remains poorly defined phenomenon and mechanistically ill understood. The TRPM2 channel has emerged as a potentially ubiquitous molecular mechanism mediating oxidative damage and thus plays a vital role in the pathogenesis and progression of diverse neurodegenerative diseases. This article will review the emerging evidence from recent studies and propose a novel ‘hypothesis’ that multiple TRPM2-mediated cellular and molecular mechanisms cascade Aβ and/or oxidative damage to AD pathologies. The ‘hypothesis’ based on these new findings discusses the prospect of considering the TRPM2 channel as a novel therapeutic target for intervening AD and age-related dementia
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