George Ellis

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The aim of this set of lectures is a systematic presentation of a 1 + 3 covariant approach to studying the geometry, dynamics, and observational properties of relativistic cosmological models. In giving (i) the basic 1 + 3 covariant relations for a cosmological fluid, the present lectures cover some of the same ground as a previous set of Cargèse lectures(More)
We present a general framework for analyzing spatially inhomogeneous cosmological dynamics. It employs Hubble-normalized scale-invariant variables which are defined within the orthonormal frame formalism, and leads to the formulation of Einstein’s field equations with a perfect fluid matter source as an autonomous system of evolution equations and(More)
SUMMARY Traditional methods of genetic study design and analysis work well under the scenario that a handful of single nucleotide polymorphisms (SNPs) independently contribute to the risk of disease. For complex diseases, susceptibility may be determined not by a single SNP, but rather a complex interplay between SNPs. For large studies involving hundreds(More)
This paper is concerned with the evolution of spatially homogeneous cosmological models with a cosmological constant. Several authors have addressed this problem. Stabell & Refsdal [1] investigated the FriedmannLemâıtre dust models, and a generalization of their results to general equation of state appear in [2,3]. The examination of Bianchi models with(More)
The existence of closed trapped surfaces need not imply a cosmological singularity when the spatial hypersurfaces are compact. This is illustrated by a variety of examples, in particular de Sitter spacetime admits many closed trapped surfaces and obeys the null convergence condition but is non-singular in the k=+1 frame.
Starting with the suggestion of Fischler and Susskind, various attempts have recently been made to apply the holographic principle to cosmology. Among these is a generalisation by Bousso which avoids the difficulties of the original proposal in the re-collapsing FLRW models. Here we take a closer look at the question of holography in cosmology with(More)
The propagation of gravitational waves or tensor perturbations in a perturbed Friedmann -Robertson -Walker universe filled with a perfect fluid is re examined. It is shown that while the shear and magnetic part of the Weyl tensor satisfy linear, homogeneous second order wave equations, for perfect fluids with a γ law equation of state satisfying 2 3 < γ <(More)
Three research studies were conducted to gauge the effects of the statewide implementation of the Maharishi Technology of the Unified Field on the Vermont Department of Corrections. Over a two and one-half year span (January 1982 through June 1984) more than 500 inmates and 200 correctional professionals learned to practice the Maharishi Technology of the(More)
We present the time drift of the cosmological redshift in a general spherically symmetric spacetime. We demonstrate that its observation would allow us to test the Copernican principle and so determine if our Universe is radially inhomogeneous, an important issue in our understanding of dark energy. In particular, when combined with distance data, this(More)