2,118 research outputs found
Fermion Generations and Mixing from Dualized Standard Model
We review a possible solution to the fermion generation puzzle based on a
nonabelian generalization of electric--magnetic duality derived some years ago.
This nonabelian duality implies the existence of another SU(3) symmetry dual to
colour, which is necessarily broken when colour is confined and so can play the
role of the ``horizontal'' symmetry for fermion generations. When thus
identified, dual colour then predicts 3 and only 3 fermion generations, besides
suggesting a special Higgs mechanism for breaking the generation symmetry. A
phenomenological model with a Higgs potential and a Yukawa coupling constructed
on these premises is shown to explain immediately all the salient qualitative
features of the fermion mass hierarchy and mixing pattern, excepting for the
moment CP-violation. Calculations already carried out to 1-loop order is shown
to give with only 3 adjustable parameters the following quantities all to
within present experimental error: all 9 CKM matrix elements for
quarks, the neutrino oscillation angles or the MNS lepton mixing matrix
elements , and the mass ratios . The special feature of this model crucial for deriving the above
results is a fermion mass matrix which changes its orientation (rotates) in
generation space with changing energy scale, a feature which is shown to have
direct empirical support.Comment: updated version of course of lectures given at the 42nd Cracow School
of Theoretical Physics, 2002, Polan
A Solution of the Strong CP Problem Transforming the theta-angle to the KM CP-violating Phase
It is shown that in the scheme with a rotating fermion mass matrix (i.e. one
with a scale-dependent orientation in generation space) suggested earlier for
explaining fermion mixing and mass hierarchy, the theta-angle term in the QCD
action of topological origin can be eliminated by chiral transformations, while
giving still nonzero masses to all quarks. Instead, the effects of such
transformations get transmitted by the rotation to the CKM matrix as the KM
phase giving, for of order unity, a Jarlskog invariant typically of
order as experimentally observed. Strong and weak CP violations
appear then as just two facets of the same phenomenon.Comment: 14 pages, 2 figure
The evaluation of partial binocular overlap on car maneuverability: A pilot study
An engineering approach to enlarge the helmet mounted display (HMD) field of view (FOV) and maintain resolution and weight by partially overlapping the binocular FOV has received renewed interest among human factors scientists. It is evident, based on the brief literature review, that any panoramic display with a binocular overlap, less than a minimum amount, annoys the viewer, degrades performance, and elicits undesirable behavior. The major finding is that across the 60 deg conditions, subjects moved their heads a greater distance (by about 5 degs on each side) than in the 180 deg condition, presumably to compensate for the lack of FOV. It is quite clear that the study, based on simple car maneuverability and two subjects, reveals differences in FOV, but nothing significant between binocular overlap levels and configurations. This tentatively indicates that some tradeoffs of binocular vision for a larger overall display FOV are acceptable
Pre-Congestion Notification (PCN) Architecture
This document describes a general architecture for flow admission and termination based on pre-congestion information in order to protect the quality of service of established, inelastic flows within a single Diffserv domain.\u
On the Corner Elements of the CKM and PMNS Matrices
Recent experiments show that the top-right corner element () of the
PMNS, like that () of the CKM, matrix is small but nonzero, and suggest
further via unitarity that it is smaller than the bottom-left corner element
(), again as in the CKM case (). An attempt in
explaining these facts would seem an excellent test for any model of the mixing
phenomenon. Here, it is shown that if to the assumption of a universal rank-one
mass matrix, long favoured by phenomenologists, one adds that this matrix
rotates with scale, then it follows that (A) by inputting the mass ratios
, and , (i) the corner elements are
small but nonzero, (ii) , , (iii)
estimates result for the ratios and , and
(B) by inputting further the experimental values of and
, (iv) estimates result for the values of the corner elements
themselves. All the inequalities and estimates obtained are consistent with
present data to within expectation for the approximations made.Comment: 9 pages, 2 figures, updated with new experimental data and more
detail
New Angle on the Strong CP and Chiral Symmetry Problems from a Rotating Mass Matrix
It is shown that when the mass matrix changes in orientation (rotates) in
generation space for changing energy scale, then the masses of the lower
generations are not given just by its eigenvalues. In particular, these masses
need not be zero even when the eigenvalues are zero. In that case, the strong
CP problem can be avoided by removing the unwanted term by a chiral
transformation in no contradiction with the nonvanishing quark masses
experimentally observed. Similarly, a rotating mass matrix may shed new light
on the problem of chiral symmetry breaking. That the fermion mass matrix may so
rotate with scale has been suggested before as a possible explanation for
up-down fermion mixing and fermion mass hierarchy, giving results in good
agreement with experiment.Comment: 14 page
Web-based Remote Sensing Applications and Java Tools for Environmental Monitoring
This paper introduces a web-based remote sensing application which can provide advanced image comparison and processing functions for natural habitat conservation and environmental monitoring. This project is one of several NASA Affiliated Research Center (ARC) projects being developed at San Diego State University in response to NASA\u27s Earth Science Enterprise (ESE) Focus Area program. This project utilized Java programming and commercial Internet Map Server technology to provide integrated web-based analytical capabilities to regional government agencies and park services.
A prototype website (http://map.sdsu.edu/arc) was established to demonstrate the on-line analytical functions and potential operational applications for environmental monitoring and habitat managers. The web-based prototype was tested and evaluated by several user groups, including park rangers, graduate students, and GIS professionals. Users\u27 feedback indicated that the Java-based tools and Internet Map Servers can provide a flexible way to access both remote sensing data and geospatial analytical tools for environmental monitoring tasks
Closed-loop carrier phase synchronization techniques motivated by likelihood functions
This article reexamines the notion of closed-loop carrier phase synchronization motivated by the theory of maximum a posteriori phase estimation with emphasis on the development of new structures based on both maximum-likelihood and average-likelihood functions. The criterion of performance used for comparison of all the closed-loop structures discussed is the mean-squared phase error for a fixed-loop bandwidth
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