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The cosmological constant is back [PDF]
General Relativity and Gravitation, 1995 A diverse set of observations now compellingly suggest that Universe possesses a nonzero cosmological constant. In the context of quantum-field theory a cosmological constant corresponds to the energy density of the vacuum, and the wanted value for the cosmological constant corresponds to a very tiny vacuum energy density.
Krauss Lawrence M, Turner Michael S
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The cosmological constant problem [PDF]
Reviews of Modern Physics, 1989 Summary: Astronomical observations indicate that the cosmological constant is many orders of magnitude smaller than estimated in modern theories of elementary particles. After a brief review of the history of this problem, five different approaches to its solution are described.
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Cosmological constant—the weight of the vacuum [PDF]
Physics Reports, 2003 Recent cosmological observations suggest the existence of a positive cosmological constant Λ with the magnitude Λ (Gh/c3)≈ 10-123. This review discusses several aspects of the cosmological constant both from the cosmological (Sections 1-6)
Thanu Padmanabhan
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Relaxation of the cosmological constant [PDF]
Physical Review D, 2019 We present a model that naturally tunes a large positive cosmological constant to a small cosmological constant. A slowly rolling scalar field decreases the cosmological constant to a small negative value, causing the universe to contract, thus reheating it. An expanding universe with a small positive cosmological constant can be obtained, respectively,
Surjeet Rajendran +2 more
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Nature, 1937
THE fundamental constants of physics, such as c the velocity of light, h Planck's constant, e the charge and m mass of the electron, and so on, provide for us a set of absolute units for measurement of distance, time, mass, etc. There are, however, more of these constants than are necessary for this purpose, with the result that certain dimensionless ...
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THE fundamental constants of physics, such as c the velocity of light, h Planck's constant, e the charge and m mass of the electron, and so on, provide for us a set of absolute units for measurement of distance, time, mass, etc. There are, however, more of these constants than are necessary for this purpose, with the result that certain dimensionless ...
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The cosmological constant and cosmological change
Physics Today, 1977Is the Universe of infinite extent, or is it a finite system? Will it expand forever, or will it reach some maximum size before turning and collapsing upon itself like an inverse Big Bang? Just a few years ago, models of the conventional Friedman types were showing consistent, albeit tentative, evidence for an open, ever-expanding Universe. Since then,
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ON THE COSMOLOGICAL CONSTANT AS A CONSTANT OF INTEGRATION
Modern Physics Letters A, 1991The possibilities to construct a modification of General Relativity (MGR), where the cosmological constant appears as a constant of integration are considered. A class of new constraints on the metric is found, such that their inclusion in the Hilbert–Einstein action before its variation leads to MGR.
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ANOTHER “COSMOLOGICAL” CONSTANT
International Journal of Modern Physics A, 1992Capovilla, Jacobson and Dell have found a one-parameter family of field equations which coincides with Einstein’s equations when the parameter is set to zero. The basic variable is an SO(3) vector potential. For generic values of the parameter, we show that the solutions of the field equations may be interpreted in terms of Riemannian geometry.
Bengtsson, Ingemar, Peldán, Peter
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Astrophysics and Space Science, 2003
We review varying speed of light (VSL) theories, in a cosmological and astrophysical setting, and as phenomenological descriptions of quantum gravity. We first introduce two observational puzzles, and explain how they may related to VSL. We then catalogue the various theoretical efforts associated with VSL. We focus on recent VSL theories rendering the
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We review varying speed of light (VSL) theories, in a cosmological and astrophysical setting, and as phenomenological descriptions of quantum gravity. We first introduce two observational puzzles, and explain how they may related to VSL. We then catalogue the various theoretical efforts associated with VSL. We focus on recent VSL theories rendering the
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EFFECTIVE COSMOLOGICAL CONSTANT IN BRANE COSMOLOGY
International Journal of Modern Physics D, 2006We consider a brane-world of co-dimension one without reflection symmetry. Through it, we give a possible explanation of the great discrepancy between the vacuum energy and the observed cosmological constant without contradiction to the knowledge we have about our Universe. We also show the gravity observed will be standard four-dimensional gravity as
Hu, Sen, Wang, Jing-Rong
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