3,461 research outputs found
Classicalization of Quantum Fluctuation in Inflationary Universe
We discuss the classicalization of a quantum state induced by an environment
in the inflationary stage of the universe. The classicalization is necessary
for the homogeneous ground sate to become classical non-homogeneous one
accompanied with the statistical fluctuation, which is a plausible candidate
for the seeds of structure formation. Using simple models, we show that i) the
two classicalization criteria, the classical correlation and quantum
decoherence, are simultaneously satisfied by the environment and that ii) the
power spectrum of the resultant statistical fluctuation depends upon the detail
of the classicalization process. Especially, the result ii) means that, taking
account of the classicalization process, the inflationary scenario does not
necessarily predict the unique spectrum which is usually believed.Comment: 24 pages, Latex, 2 Postscript figure
Liquid phase epitaxy of GaAlAs on GaAs substrates with fine surface corrugations
Liquid phase epitaxy of GaAlAs was performed on GaAs fine surface corrugations. By optimizing the growth conditions, GaAlAs layers were grown successfully with only minimal meltback
Large- meson theory
We derive an effective Lagrangian for meson fields. This is done in the light-cone gauge for two-dimensional large-N_c QCD by using the bilocal auxiliary field method. The auxiliary fields are bilocal on light-cone space and their Fourier transformation determines the parton momentum distribution. As the first test of our method, the 't Hooft equation is derived from the effective Lagrangian
Development of hydrogen masers for K-3 VLBI system
Two field operable hydrogen masers were developed for the VLBI joint experiment conducted by the cooperation between RRL and NASA. They are now playing an important role as the time and frequency standard of the K-3 VLBI system, which has also been developed by RRL
Scaling Relations for Collision-less Dark Matter Turbulence
Many scaling relations are observed for self-gravitating systems in the
universe. We explore the consistent understanding of them from a simple
principle based on the proposal that the collision-less dark matter fluid terns
into a turbulent state, i.e. dark turbulence, after crossing the caustic
surface in the non-linear stage. The dark turbulence will not eddy dominant
reflecting the collision-less property. After deriving Kolmogorov scaling laws
from Navier-Stokes equation by the method similar to the one for Smoluchowski
coagulation equation, we apply this to several observations such as the
scale-dependent velocity dispersion, mass-luminosity ratio, magnetic fields,
and mass-angular momentum relation, power spectrum of density fluctuations.
They all point the concordant value for the constant energy flow per mass: , which may be understood as the speed of the hierarchical
coalescence process in the cosmic structure formation.Comment: 26 pages, 6 figure
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