1,575 research outputs found
Holographic principle and large scale structure in the universe
A reasonable representation of large scale structure, in a closed universe so
large it's nearly flat, can be developed by extending the holographic principle
and assuming the bits of information describing the distribution of matter
density in the universe remain in thermal equilibrium with the cosmic microwave
background radiation. The analysis identifies three levels of self-similar
large scale structure, corresponding to superclusters, galaxies, and star
clusters, between today's observable universe and stellar systems. The
self-similarity arises because, according to the virial theorem, the average
gravitational potential energy per unit volume in each structural level is the
same and depends only on the gravitational constant. The analysis indicates
stellar systems first formed at z\approx62, consistent with the findings of
Naoz et al, and self-similar large scale structures began to appear at redshift
z\approx4. It outlines general features of development of self-similar large
scale structures at redshift z<4. The analysis is consistent with observations
for angular momentum of large scale structures as a function of mass, and
average speed of substructures within large scale structures. The analysis also
indicates relaxation times for star clusters are generally less than the age of
the universe and relaxation times for more massive structures are greater than
the age of the universe.Comment: Further clarification of assumptions underlying the analysi
Holography, charge and baryon asymmetry
The reason for baryon asymmetry in our universe has been a pertinent question
for many years. The holographic principle suggests a charged preon model
underlies the Standard Model of particle physics and any such charged preon
model requires baryon asymmetry. This note estimates the baryon asymmetry
predicted by charged preon models in closed inflationary Friedmann universes.Comment: 5 pages, no figures, clarified discussion of comparison with
observation
Scaling Law for the Cosmological Constant from Quantum Cosmology with Seven Extra Dimensions
According to a model of quantum cosmology the maximum number of degrees of
freedom allowed in our three dimensions was determined by the size of seven
extra dimensions in an initial excited state before inflation. The size of the
extra dimensions can be inferred from a simple scheme for unifying the strong
force and gravity. Coupled with the Bekenstein-Hawking entropy bound, these
considerations lead to a scaling law for the cosmological constant that has
been proposed independently by several authors.Comment: matches published version in IJT
Holography and non-locality in a closed vacuum-dominated universe
A closed vacuum-dominated Friedmann universe is asymptotic to a de Sitter
space with a cosmological event horizon for any observer. The holographic
principle says the area of the horizon in Planck units determines the number of
bits of information about the universe that will ever be available to any
observer. The wavefunction describing the probability distribution of mass
quanta associated with bits of information on the horizon is the boundary
condition for the wavefunction specifying the probability distribution of mass
quanta throughout the universe. Local interactions between mass quanta in the
universe cause quantum transitions in the wavefunction specifying the
distribution of mass throughout the universe, with instantaneous non-local
effects throughout the universe.Comment: 4 pages, no figures, to be published in Int. J. Theor. Phys,
references correcte
Health financing: challenges and opportunities, coverage and cost
This policy panel will present and debate proposals for the next steps in reforming the U.S. health care system. Which challenge deserves the highest priority – providing universal access; instituting better measures of quality and outcomes and better management systems; or reining in costs? How should these challenges be addressed? What keeps us from “having it all”? Does the fundamental obstacle lie in market behavior, inadequate or asymmetric information, lack of political will, or the human psyche? How would the proposed reforms tackle the underlying issue and help us maintain a sustainable balance between health care access, quality and cost – and between our health care goals and other important policy objectives – in future years?Health care reform
Evidence for the existence of new processes at energies above 2 times 10 11 eV
Cosmic ray flux measurements using calorimeter
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