Results 31 to 40 of about 16,133 (302)
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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Mirror QCD and Cosmological Constant
Universe, 2017 An analog of Quantum Chromo Dynamics (QCD) sector known as mirror QCD (mQCD) can affect the cosmological evolution due to a non-trivial contribution to the Cosmological Constant analogous to that induced by the ground state in non-perturbative QCD.
Roman Pasechnik +2 more
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The cosmological constant is probably still zero [PDF]
, 2023 We consider a wide class of four-dimensional effective field theories in which gravity is coupled to multiple four-forms and their dual scalar fields, with membrane sources charged under the corresponding three-form potentials.
Liu, Yang +2 more
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Proposal for a constant cosmological constant [PDF]
Physics Letters B, 2000 12 pages, LaTeX, 1 figure; minor rewriting, references corrected, results ...
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Wormholes and the cosmological constant [PDF]
Nuclear Physics B, 1989 We review Coleman's wormhole mechanism for the vanishing of the cosmological constant. We show that in a minisuperspace model wormhole-connected universes dominate the path integral. We also provide evidence that the euclidean path integral over geometries with spherical topology is unstable with respect to formation of infinitely many wormhole ...
Igor KLEBANOV +2 more
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A symmetry for the cosmological constant [PDF]
Journal of High Energy Physics, 2006 We study a symmetry, schematically Energy -> - Energy, which suppresses matter contributions to the cosmological constant. The requisite negative energy fluctuations are identified with a "ghost" copy of the Standard Model. Gravity explicitly, but weakly, violates the symmetry, and naturalness requires General Relativity to break down at short ...
Kaplan, David E., Sundrum, Raman
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Cosmological Bounce and the Cosmological Constant Problem
SSRN Electronic Journal, 2022 32 pages, 9 ...
Pavlović, Petar, Sossich, Marko
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Lemaître Class Dark Energy Model for Relaxing Cosmological Constant
Universe, 2017 Cosmological constant corresponds to the maximally symmetric cosmological term with the equation of state p = − ρ . Introducing a cosmological term with the reduced symmetry, p r = − ρ in the spherically symmetric case, makes ...
Irina Dymnikova +2 more
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Modified gravity with disappearing cosmological constant
Journal of High Energy Physics, 2021 New corrections to General Relativity are considered in the context of modified f(R) gravity, that satisfy cosmological and local gravity constraints. The proposed models behave asymptotically as R − 2Λ at large curvature and show the vanishing of the ...
L. N. Granda
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AN ADJUSTABLE COSMOLOGICAL CONSTANT [PDF]
Physics Beyond the Standard Models of Particles, Cosmology and Astrophysics, 2011 Jihn E. Kim Department of Physics and Astronomy and Center for Theoretical Physics, Seoul National University, Seoul 151-747, Korea DOI: http://dx.doi.org/10.3204/DESY-PROC-2010-03/kim jihn After showing the axion couplings, I review the Hawking type solution of the cosmological constant problem, present a (probably) correct way to calculate the ...
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