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Cosmological constant as a fundamental constant⋆ [PDF]
The European Physical Journal Plus, 2019 Eur Phys J Plus, to appear, 5 ...
Gurzadyan, V. G., Stepanian, A.
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Unified Dark Matter models with fast transition [PDF]
, 2010 We investigate the general properties of Unified Dark Matter (UDM) fluid models where the pressure and the energy density are linked by a barotropic equation of state (EoS) p = p(ρ) and the perturbations are adiabatic.
Davide Pietrobon +12 more
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THE COSMOLOGICAL CONSTANT [PDF]
String Phenomenology, 2003 Various contributions to the cosmological constant are discussed and confronted with its recent measurement. We briefly review different scenarious -- and their difficulties -- for a solution of the cosmological constant problem.
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Dilatations and the cosmological constant [PDF]
Nuclear Physics B, 1989 Abstract The role of dilatation symmetry in explaining the smallness of the cosmological constant is investigated. Dilatation-invariant theories necessarily lead to a zero cosmological constant, but only if the vacuum is invariant. This is physically unacceptable, and dilatation invariance must be broken (at least) spontaneously, in which case we do ...
Coughlan, G, Kani, I, Ross, G, Segre, G
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Is There a Cosmological Constant? [PDF]
The Astrophysical Journal, 1996 We present limits on the cosmological constant from the statistics of gravitational lenses using newly completed quasar surveys, new lens data, and a range of lens models. The formal limit is $λ_0 < 0.66$ at 95\% confidence in flat cosmologies, including the statistical uncertainties in the number of lenses, galaxies, quasars, and the parameters ...
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Bootstrapped Newtonian Cosmology and the Cosmological Constant Problem [PDF]
Symmetry, 2021 Bootstrapped Newtonian gravity was developed with the purpose of estimating the impact of quantum physics in the nonlinear regime of the gravitational interaction, akin to corpuscular models of black holes and inflation. In this work, we set the ground for extending the bootstrapped Newtonian picture to cosmological spaces.
Casadio, Roberto, Giusti, Andrea
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Is the Zero-Point Energy Real? [PDF]
, 2002 I consider the arguments to show that the vacuum energy density should receive a large contribution from the zero-point energy. This is the cosmological constant problem, as it was originally framed. I suggest that the matter is interpretation-dependent,
Simon Saunders, Saunders, Simon
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On Einstein’s early interpretation of the cosmological constant [PDF]
, 2012 When Einstein modified his gravitational field equations by introducing the cosmological constant, he did so for cosmological reasons. But he also tried to see whether the field equations could be interpreted as being constitutive for the ...
T. Sauer, Sauer, Tilman
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Cosmology with varying constants [PDF]
Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2001 14 pages, no figures. Essay to appear in Phil. Trans. Roy. Soc. Lond. A Triennial Series (Christmas 2002 Issue)
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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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