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Particle horizon

About: Particle horizon is a research topic. Over the lifetime, 2096 publications have been published within this topic receiving 69137 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the concept of internal time is applied to a cosmological model having spatial hypersurfaces of negative curvature, and it is then possible to ascribe an irreversible evolution to the expanding universe without resorting to any coarse graining or "loss of information".
Abstract: The concept of "internal time" is applied to a cosmological model having spatial hypersurfaces of negative curvature. It is then possible to ascribe an irreversible evolution to the expanding universe without resorting to any "coarse graining" or "loss of information." The key observation which enables this description to be used is that geodesic flow on a four-manifold can be reduced to geodesic flow on a three-manifold when the Robertson-Walker metric is used. If the three-surface is compactified in such a way as not to change the metric, and if it has negative curvature, the geodesic system is a Bernoulli flow a dynamical system which has the highest degree of instability. We draw various conclusions about mixing in the system pertinent to the microwave background, the observational consequences of negative curvature for objects moving with respect to the galaxies, and we show that the requirement of negative curvature always leads to a particle horizon, a conclusion which has some bearing on the physical spectrum of the internal time operator and on the possibility of removing the cosmological singularity to the infinite past. © 1982 The American Physical Society.

44 citations

Journal ArticleDOI
TL;DR: Using a long wavelength iteration scheme to solve Einstein's equations near the big-bang singularity of a universe driven by a massive scalar field, this work finds how big initial quasi-isotropic inhomogeneities can be before they can prevent inflation to set in.
Abstract: Using a long wavelength iteration scheme to solve Einstein's equations near the big-bang singularity of a universe driven by a massive scalar field, we find how big initial quasi-isotropic inhomogeneities can be before they can prevent inflation to set in.

44 citations

Book
04 Nov 1994
TL;DR: The problem of large-scale structure of the universe geometry, dynamical systems, catastrophes definition of a galaxy cluster the bound-tree technique appearance of matter distribution statistical methods filaments and light-travel effects the cosmic background radiation as a tracer of geometry as mentioned in this paper.
Abstract: The problem of large-scale structure of the universe geometry, dynamical systems, catastrophes definition of a galaxy cluster the bound-tree technique appearance of matter distribution statistical methods filaments and light-travel effects the cosmic background radiation as a tracer of geometry of the universe

44 citations

Journal ArticleDOI
TL;DR: In this article, the notion of a typical quantum state for the universe is discussed and it appears that inflation is a typical property of solutions of the Wheeler-DeWitt equation.

44 citations

Journal ArticleDOI
TL;DR: It is shown that the supernovae results, which imply that there is evidence for an accelerating universe, may be closely related to the recent discovery of redshift dependence in the fine-structure constant alpha.
Abstract: We show that the supernovae results, which imply that there is evidence for an accelerating universe, may be closely related to the recent discovery of redshift dependence in the fine-structure constant alpha. The link is a class of varying speed-of-light (VSL) theories that contain cosmological solutions that are similar to quintessence. During the radiation-dominated epoch, the cosmological constant Lambda is prevented from dominating the universe by the usual VSL mechanism. In the matter-dominated epoch, the varying-c effects switch off, allowing Lambda to eventually surface and lead to an accelerating universe. By the time this happens, the residual variations in c imply a changing alpha at a rate that is in agreement with observations.

44 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202320
202247
20216
202010
201910
201814