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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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The cosmological frame principle and cosmic acceleration
European Physical Journal C: Particles and Fields, 2023 We discuss implications of the cosmological frame principle which states that cosmological effects of modified gravity must be stable as solutions of each of the corresponding sets of dynamical equations holding in the two conformally-related frames.
Spiros Cotsakis +2 more
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A tilt instability in the cosmological principle
European Physical Journal C: Particles and Fields, 2023 We show that the Friedmann–Lemaître–Robertson–Walker (FLRW) framework has an instability towards the growth of fluid flow anisotropies, even if the Universe is accelerating. This flow (tilt) instability in the matter sector is invisible to Cosmic No-Hair
Chethan Krishnan +2 more
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A Comparative Study on the Degree of Dependence of Clarke’s and Sadra’s Arguments for the Existence of God on the Principle of Sufficient Reason [PDF]
حکمت و فلسفه, 2010 After briefly discussing the various versions of the Principle of Sufficient Reason (hereafter PSR), I argue that Clarke’s classic version of the Cosmological Arguments for the existence of God is rooted in the PSR, while Sadra’s so-called Siddigin ...
hasan hoseyni
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Sakarya Üniversitesi Fen Bilimleri Enstitüsü Dergisi, 2022 In this study, we investigate the effect of the generalized uncertainty principle on the ΛCDM cosmological model. Using quantum corrected Unruh effect and Verlinde’s entropic gravity idea, we find Planck-scale corrected Friedmann equations with a ...
Salih Kibaroğlu
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Large Scale Cosmological Anomalies and Inhomogeneous Dark Energy
Galaxies, 2014 A wide range of large scale observations hint towards possible modifications on the standard cosmological model which is based on a homogeneous and isotropic universe with a small cosmological constant and matter.
Leandros Perivolaropoulos
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European Physical Journal C: Particles and Fields, 2021 We consider a cosmological scenario endowed with an interaction between the universe’s dark components – dark matter and dark energy. Specifically, we assume the dark matter component to be a pressure-less fluid, while the dark energy component is a ...
Andronikos Paliathanasis +4 more
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Odessa Astronomical Publications, 2017 The basis of this work is the scheme for describing the universe, called the ”cosmography” entirely based on the cosmological principle. Within the framework of such a scheme the parameters of any model that satisfies the cosmological principle (the ...
Yu. L. Bolotin +3 more
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Cosmological constant from a deformation of the Wheeler–DeWitt equation
Nuclear Physics B, 2016 In this paper, we consider the Wheeler–DeWitt equation modified by a deformation of the second quantized canonical commutation relations. Such modified commutation relations are induced by a Generalized Uncertainty Principle.
Remo Garattini, Mir Faizal
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Linear and quadratic GUP, Liouville theorem, cosmological constant, and Brick Wall entropy
European Physical Journal C: Particles and Fields, 2019 Motivated by the works on equivalence principle in the context of linear generalized uncertainty principle and, independently, in the context of quadratic generalized uncertainty principle, we expand these endeavors in the context of generalized ...
Elias C. Vagenas +3 more
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