5,445 research outputs found
Fine-tuning and naturalness issues in the two-zero neutrino mass textures
In this paper we analyze the compatibility of two-zero neutrino Majorana
textures with the recent experimental data. Differently from previous works, we
use the experimental data to fix the values of the non-vanishing mass matrix
entries and study in detail the correlations and degree of fine-tuning among
them, which is also a measure of how naturally a given texture is able to
describe all neutrino data. This information is then used to expand the
textures in powers of the Cabibbo angle; extracting random O(1) coefficients,
we show that only in few cases such textures reproduce the mixing parameters in
their 3 sigma ranges.Comment: 13 pages, 14 figures. Version to appear in NP
Four Zero Texture Fermion Mass Matrices in SO(10) GUT
We attempt the integration of the phenomenologically successful four zero
texture of fermion mass matrices with the renormalizable SO(10) GUT. The
resulting scenario is found to be highly predictive. Firstly, we examine the
phenomenological implications of a class of the lepton mass matrices with
parallel texture structures and obtain interesting constraints on the
parameters of the charged lepton and the neutrino mass matrices. We combine
these phenomenological constraints with the constraints obtained from SO(10)
GUT to reduce the number of the free parameters and to further constrain the
allowed ranges of the free parameters. The solar/atmospheric mixing angles
obtained in this analysis are in fairly good agreement with the data.Comment: 14 pages, 3 figures, 1 tabl
The consequences of SU(3) colorsingletness, Polyakov Loop and Z(3) symmetry on a quark-gluon gas
Based on quantum statistical mechanics we show that the color singlet
ensemble of a quark-gluon gas exhibits a symmetry through the normaized
character in fundamental representation and also becomes equivalent, within a
stationary point approximation, to the ensemble given by Polyakov Loop. Also
Polyakov Loop gauge potential is obtained by considering spatial gluons along
with the invariant Haar measure at each space point. The probability of the
normalized character in vis-a-vis Polyakov Loop is found to be maximum
at a particular value exhibiting a strong color correlation. This clearly
indicates a transition from a color correlated to uncorrelated phase or
vise-versa. When quarks are included to the gauge fields, a metastable state
appears in the temperature range due to the
explicit symmetry breaking in the quark-gluon system. Beyond
MeV the metastable state disappears and stable domains appear. At low
temperature a dynamical recombination of ionized color charges to a
color singlet confined phase is evident along with a confining
background that originates due to circulation of two virtual spatial gluons but
with conjugate phases in a closed loop. We also discuss other possible
consequences of the center domains in the color deconfined phase at high
temperature.Comment: Version published in J. Phys.
Composite Fermions and Landau Level Mixing in the Fractional Quantum Hall Effect
The reduction of the energy gap due to Landau level mixing, characterized by
the dimensionless parameter , has
been calculated by variational Monte Carlo for the fractional quantum Hall
effect at filling fractions and 1/5 using a modified version of
Jain's composite fermion wave functions. These wave functions exploit the
Landau level mixing already present in composite fermion wave functions by
introducing a partial Landau level projection operator. Results for the energy
gaps are consistent with experimental observations in -type GaAs, but we
conclude that Landau level mixing alone cannot account for the significantly
smaller energy gaps observed in -type systems.Comment: 11 pages, RevTex, 2 figures in compressed tar .ps forma
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