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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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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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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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Collapse Models and Cosmology [PDF]
, 2020 minor typo in equation (30) corrected, conclusions and results ...
Martin, Jérôme, Vennin, Vincent
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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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Errant Man: The Importance of Cosmological Models in Culture [PDF]
Философия и космология, 2019 The author considers the meanings of the term “errant man” in the paper. The birth of man is his abandonment in being and wandering in it. It is important that wandering in being have direction, the source that drives man, forms the authenticity ...
Iryna Dobroskok
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On model selection in cosmology [PDF]
SciPost Physics Lecture Notes, 2019 We review some of the common methods for model selection: the goodness of fit, the likelihood ratio test, Bayesian model selection using Bayes factors, and the classical as well as the Bayesian information theoretic approaches. We illustrate these different approaches by comparing models for the expansion history of the Universe.
Kerscher, Martin, Weller, Jochen
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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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