Results 11 to 20 of about 197,812 (267)
Homogeneous cosmologies with cosmological constant [PDF]
Physical Review D, 1999 Spatially homogeneous cosmological models with a positive cosmological constant are investigated, using dynamical systems methods. We focus on the future evolution of these models.
A. A. Coley +36 more
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The Cosmological Constant [PDF]
Annual Review of Astronomy and Astrophysics, 1992 50 pages.
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Deconstructing the Cosmological Constant
, 2003 Deconstruction provides a novel way of dealing with the notoriously difficult ultraviolet problems of four-dimensional gravity. This approach also naturally leads to a new perspective on the holographic principle, tying it to the fundamental requirements
Jejjala, Vishnu +2 more
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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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Living Reviews in Relativity, 2001 This is a review of the physics and cosmology of the cosmological constant. Focusing on recent developments, I present a pedagogical overview of cosmology in the presence of a cosmological constant, observational constraints on its magnitude, and the ...
Carroll Sean M.
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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 ...
B. Chaboyer +17 more
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Cosmological constant from decoherence [PDF]
Classical and Quantum Gravity, 2011 We address the issue why a cosmological constant (dark energy) possesses a small positive value instead of being zero. Motivated by the cosmic landscape picture, we mimic the dark energy by a scalar field with potential wells and show that other degrees of freedom interacting with it can localize this field by decoherence in one of the wells.
Kiefer, Claus +2 more
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Inflation and cosmological constant [PDF]
Physica Scripta, 2021 Abstract In construction of an inflationary model, one usually assumes that the matter sector of the gravitational action is minimally coupled to the background. It means that the matter (inflaton) part of the action is coupled with the same metric of the gravitational part.
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Loop quantum gravity and cosmological constant
Physics Letters B, 2021 A one-parameter regularization freedom of the Hamiltonian constraint for loop quantum gravity is analyzed. The corresponding spatially flat, homogenous and isotropic model includes the two well-known models of loop quantum cosmology as special cases. The
Xiangdong Zhang, Gaoping Long, Yongge Ma
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Inflation and the cosmological constant
上海师范大学学报. 自然科学版, 2014 By assuming the cosmological “constant” is no longer a constant during the inflation epoch,it is found that the cosmological constant fine-tuning problem is solved.In the meanwhile,inflation models could predict a large tensor-to-scalar ratio,correct ...
FENG Chaojun, LI Xinzhou
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