2,446 research outputs found
Phenomenology of Neutrino Mass Matrix
The search for possible mixing patterns of charged leptons and neutrinos is
important to get clues of the origin of nearly maximal mixings, since there are
some preferred bases of the lepton mass matrices given by underlying theories.
We systematically examine the mixing patterns which could lead to large lepton
mixing angles. We find out 37 mixing patterns are consistent with experimental
data if taking into account phase factors in the mixing matrices. Only 6
patterns of them can explain the observed data without any tuning of
parameters, while the others need particular choices for phase values.Comment: revised reference
5-State Rotation-Symmetric Number-Conserving Cellular Automata are not Strongly Universal
We study two-dimensional rotation-symmetric number-conserving cellular
automata working on the von Neumann neighborhood (RNCA). It is known that such
automata with 4 states or less are trivial, so we investigate the possible
rules with 5 states. We give a full characterization of these automata and show
that they cannot be strongly Turing universal. However, we give example of
constructions that allow to embed some boolean circuit elements in a 5-states
RNCA
Representation theory of the stabilizer subgroup of the point at infinity in Diff(S^1)
The group Diff(S^1) of the orientation preserving diffeomorphisms of the
circle S^1 plays an important role in conformal field theory. We consider a
subgroup B_0 of Diff(S^1) whose elements stabilize "the point of infinity".
This subgroup is of interest for the actual physical theory living on the
punctured circle, or the real line. We investigate the unique central extension
K of the Lie algebra of that group. We determine the first and second
cohomologies, its ideal structure and the automorphism group. We define a
generalization of Verma modules and determine when these representations are
irreducible. Its endomorphism semigroup is investigated and some unitary
representations of the group which do not extend to Diff(S^1) are constructed.Comment: 34 pages, no figur
Neutrino masses and mixing from S4 flavor twisting
We discuss a neutrino mass model based on the S4 discrete symmetry where the
symmetry breaking is triggered by the boundary conditions of the bulk
right-handed neutrino in the fifth spacial dimension. While the symmetry
restricts bare mass parameters to flavor-diagonal forms, the viable mixing
angles emerge from the wave functions of the Kaluza-Klein modes which carry
symmetry breaking effect. The magnitudes of the lepton mixing angles,
especially the reactor angle is related to the neutrino mass patterns and the
model will be tested in future neutrino experiments, e.g., an early (late)
discovery of the reactor angle favors the normal (inverted) hierarchy. The size
of extra dimension has a connection to the possible mass spectrum; a small
(large) volume corresponds to the normal (inverted) mass hierarchy.Comment: 22 pages, 3 figures; added references for section
Leptogenesis and Low energy CP violation, a link
How is CP violation of low energy related to CP violation required from
baryon number asymmetry ? We give an example which shows a direct link between
CP violation of neutrino oscillation and baryogenesis through leptogenesis.Comment: 3 pages and 2 figures, Talk presented at 4th Nufac02, July 1-6, 200
In-roll stress analysis of wound roll with the air entrainment and the permeation
The quality of a wound roll is highly dependent upon the in-roll stress distribution, which is controlled by the operating parameters of center torque, nip and tension. With increasing demands for higher performance of paper winding machines in terms of higher speed of winding, wider width of web and larger diameter of wound rolls, it becomes of vital importance to determine the optimum operating conditions of the machines.In this paper, a numerical formulation for estimating the in-roll stress of a wound roll is proposed taking account of the effect of nonlinearity in web compressibility, air-entrainment and permeance. The proposed theory of winding is based on the assumption that the accumulation of the in-roll stress by a wound-in layer can be expressed as the superposition of the stress increments calculated from a mechanical model of a pressured thick cylinder. The theory of elasto-hydrodynamic lubrication with the compressibility of air is introduced to evaluate the effect of air-entrainment at the roll-inlet. Permeance of air is newly incorporated into the winding model, which is expressed under the assumption that permeance is proportional to the pressure difference of both sides of a web.Winding tests were conducted in order to assure the applicability of the proposed theory by usage of the dry-end section of the paper-making pilot machine under the operating conditions of 200 - 2000m/min in winding speed, 765mm in web width and 1200mm in diameter of the wound roll. The numerical analysis and experimental observation shows the significant effect of the air-entrainment and permeance upon the in-roll stress
Affect of Cardiac Complications After Allogeneic Hematopoietic Stem Cell Transplantation From Various Stem Cell Sources
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