29 research outputs found
Radiative Generation of the LMA Solution from Small Solar Neutrino Mixing at the GUT Scale
We show that in see-saw models with small or even vanishing lepton mixing
angle , maximal , zero and zero CP
phases at the GUT scale, the currently favored LMA solution of the solar
neutrino problem can be obtained in a rather natural way by Renormalization
Group effects. We find that most of the running takes place in the energy
ranges above and between the see-saw scales, unless the charged lepton Yukawa
couplings are large, which would correspond to a large in the
Minimal Supersymmetric Standard Model (MSSM). The Renormalization Group
evolution of the solar mixing angle is generically larger than
the evolution of and . A large enhancement occurs
for an inverted mass hierarchy and for a regular mass hierarchy with . We present numerical examples of the evolution of the
lepton mixing angles in the Standard Model and the MSSM, in which the current
best-fit values of the LMA mixing angles are produced with vanishing solar
mixing angle at the GUT scale.Comment: 10 pages, 6 figures; reference added, minor changes in the text;
results unchanged; final version to appear in JHE
Predictions for Proton Lifetime in Minimal Non-Supersymmetric SO(10) Models: An Update
We present our best estimates of the uncertainties due to heavy particle
threshold corrections on the unification scale , intermediate scale
and coupling constant Alpha_U in the minimal non-supersymmetric SO(10) models.
Using these , we update the predictions for proton life-time in these models.Comment: UMD-PP-94-117 ( 20 pages;latex; no figures
Project management between will and representation
This article challenges some deep-rooted assumptions of project management. Inspired by the work of the German philosopher, Arthur Schopenhauer, it calls for looking at projects through two complementary lenses: one that accounts for cognitive and representational aspects and one that accounts for material and volitional aspects. Understanding the many ways in which these aspects transpire and interact in projects sheds new light on project organizations, as imperfect and fragile representations that chase a shifting nexus of intractable human, social, technical, and material processes. This, in turn, can bring about a new grasp of notions such as value,\ud
knowledge, complexity, and risk
Prospects for e+e- physics at Frascati between the phi and the psi
We present a detailed study, done in the framework of the INFN 2006 Roadmap,
of the prospects for e+e- physics at the Frascati National Laboratories. The
physics case for an e+e- collider running at high luminosity at the phi
resonance energy and also reaching a maximum center of mass energy of 2.5 GeV
is discussed, together with the specific aspects of a very high luminosity
tau-charm factory. Subjects connected to Kaon decay physics are not discussed
here, being part of another INFN Roadmap working group. The significance of the
project and the impact on INFN are also discussed. All the documentation
related to the activities of the working group can be found in
http://www.roma1.infn.it/people/bini/roadmap.html.Comment: INFN Roadmap Report: 86 pages, 25 figures, 9 table