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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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Universe, 2020 The stage of a super-early (primordial) scale-invariant Universe is considered on the basis of the Poincaré–Weyl gauge theory of gravity in a Cartan–Weyl space-time. An approximate solution has been found that demonstrates an inflationary behavior of the
Ol’ga Babourova, Boris Frolov
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Dark matter from torsion in Friedmann cosmology
European Physical Journal C: Particles and Fields, 2022 A cosmological model in an Einstein–Cartan framework endowed with torsion is studied. For a torsion function assumed to be proportional to Hubble expansion function, namely $$\phi =-\alpha H$$ ϕ = - α H , the contribution of torsion function as a dark ...
S. H. Pereira +3 more
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Hiding the Cosmological Constant [PDF]
Physical Review Letters, 2019 9+1 pages; v2: better discussion of evolution,m new references, some rewriting for clarity; v3: even better discussion of evolution, added references, minor ...
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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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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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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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Black hole shadow with a cosmological constant for cosmological observers
European Physical Journal C: Particles and Fields, 2019 We investigate the effect of the cosmological constant on the angular size of a black hole shadow. It is known that the accelerated expansion which is created by the cosmological constant changes the angular size of the black hole shadow for static ...
Javad T. Firouzjaee, Alireza Allahyari
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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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