333 research outputs found
Non-perturbative unification in the light of LEP results
We consider an alternative to conventional GUTs originally proposed by
Maiani, Parisi and Petronzio, where owing to the existence of extra fermion
generations at some intermediate scale, the gauge couplings become large at
high energies. We first comment on how the non- supersymmetric version of this
scenario is ruled out; we then consider the two-loop evolution of the couplings
in the supersymmetric extension of this scenario, and check whether such a
scenario is feasible in the light of the precies values of couplings now
available from LEP.Comment: Latex file 7 pages+1 fig. (ps file appended after the latex file),
CERN-TH.6913/9
Effects of an intermediate scale in SUSY grand unification
We discuss the production of lepton flavor violation and EDMs and the
viability of the unification hypothesis in SUSY grand unification with
an intermediate gauge symmetry breaking scale.Comment: 3 pages (Latex, esprc2.sty used), talk given at 4th International
Conference on Supersymmetry (SUSY '96, College Park, MD, May 29 - June 1,
1996
Constrained analytical interrelations in neutrino mixing
Hermitian squared mass matrices of charged leptons and light neutrinos in the
flavor basis are studied under general additive lowest order perturbations away
from the tribimaximal (TBM) limit in which a weak basis with mass diagonal
charged leptons is chosen. Simple analytical expressions are found for the
three measurable TBM-deviants in terms of perturbation parameters appearing in
the neutrino and charged lepton eigenstates in the flavor basis. Taking
unnatural cancellations to be absent and charged lepton perturbation parameters
to be small, interrelations are derived among masses, mixing angles and the
amount of CP-violation.Comment: To be published in the Springer Proceedings in the Physics Series
under the heading of the XXI DAE-BRNS Symposium (Guwahati, India
Structural organization of the meiotic prophase chromatin in the rat testis
Pachytene nuclei were isolated from rat testes by the unit gravity sedimentation technique and contained histone variants H1a, H1t, TH2A, TH2B, and X2 in addition to the somatic histones H1bde, H1c, H2A, H2B, H3, and H4. The basic organization of the pachytene chromatin namely the nucleosome repeat length and the accessibility to micrococcal nuclease, was similar to that of rat liver interphase chromatin. However, when digested by DNase I, the susceptibility of pachytene chromatin was 25% more than liver chromatin under identical conditions. Nucleosome core particles were isolated from both liver and pachytene nuclei and were characterized for their DNA length and integrity of the nucleoprotein on low ionic strength nucleoprotein gels. While liver core particles contained all the somatic histones H2A, H2B, H3, and H4, in the pachytene core particles, histone variants TH2A, X2, and TH2B had replaced nearly 60% of the respective somatic histones. A comparison of the circular dichroism spectra obtained for pachytene and liver core particles indicated that the pachytene core particles were less compact than the liver core particles. Studies on the thermal denaturation properties of the two types of core particles revealed that the fraction of the pachytene core DNA melting at the premelting temperature region of 55-60 degrees C was significantly higher than that of the liver core DNA
Gravitational correction to SU(5) gauge coupling unification
The gravitational corrections to the gauge coupling constants of abelian and
non-abelian gauge theories has been shown to diverge quadratically. Since this
result will have interesting consequences, this has been analyzed by several
authors from different approaches. We propose to discuss this issue from a
phenomenological approach. We analyze the SU(5) gauge coupling unification and
argue that the gravitational corrections to gauge coupling constants may not
vanish when higher dimensional non-renormalizable terms are included in the
problem.Comment: 12 pages 2 figure
- âŠ