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Stability Properties of Geometrothermodynamic Cosmological Models [PDF]
Entropy, 2023 We consider a particular isotropic and homogeneous cosmological model, in which the equation of state is obtained from a thermodynamic fundamental equation by using the formalism of geometrothermodynamics (GTD).
Nurzada Beissen +5 more
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Metaphysics of cosmological models
HTS Teologiese Studies/Theological Studies, 2023 This article aims to address the metaphysical dimension of cosmological models, be they mythological, philosophical, religious or modern scientific, using multidisciplinary and transdisciplinary methodology.
Vasile Chira
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The Astrophysical Journal, 2023 We propose a model of the Universe (dubbed η CDM) featuring a controlled stochastic evolution of the cosmological quantities that is meant to render the effects of small deviations from homogeneity/isotropy on scales of 30–50 h ^−1 Mpc at late cosmic ...
Andrea Lapi +6 more
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Polynomial Affine Model of Gravity in Three-Dimensions
Universe, 2022 In this work, we explore a three-dimensional formulation of the polynomial affine model of gravity, which is a model that extends general relativity by relaxing the equivalence principle through the exclusion of the metric from the set of fundamental ...
Oscar Castillo-Felisola +6 more
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Stability Of Cosmological Models [PDF]
Symposium - International Astronomical Union, 1995 The stability problem in cosmology is studied using the equations of geodesic deviation. General conditions for stability are obtained. The method is applied to a number of cosmological models, resulting from different field theories. The results are compared with those obtained from FRW -models.
Wanas, M. I., Bakry, M. A.
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Scalar-tensor cosmological models [PDF]
Physical Review D, 1996 uuencoded compressed postscript file containing 41 pages, with 9 figures, accepted for publication in Physical Review ...
Serna, Arturo, Alimi, Jean-Michel
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Cosmological Tensions and the Transitional Planck Mass Model
The Astrophysical Journal, 2023 In this follow-up analysis, we update previous constraints on the transitional Planck mass (TPM) modified gravity model using the latest version of EFTCAMB and provide new constraints using South Pole Telescope (SPT) and Planck anisotropy data along with
Joshua A. Kable +3 more
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Spherically Symmetric Exact Vacuum Solutions in Einstein-Aether Theory
Universe, 2021 We study spherically symmetric spacetimes in Einstein-aether theory in three different coordinate systems, the isotropic, Painlevè-Gullstrand, and Schwarzschild coordinates, in which the aether is always comoving, and present both time-dependent and time-
Jacob Oost +2 more
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Cosmological Constant from Boundary Condition and Its Implications beyond the Standard Model
Universe, 2023 Standard cosmology has long been plagued by a number of persistent problems. The origin of the apparent acceleration of the cosmic expansion remains enigmatic.
Jan O. Stenflo
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Fractal Bubble cosmology: a concordant cosmological model? [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2009 Abstract The Fractal Bubble model has been proposed as a viable cosmology that does not require dark energy to account for cosmic acceleration, but rather attributes its observational signature to the formation of structure. In this Letter, it is demonstrated that, in contrast to previous findings, this model is not a good fit to ...
Kwan, Juliana +2 more
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