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Cosmological Models and Stability [PDF]
, 2014 Based on a talk at the conference "Relativity and Gravitation, 100 Years after Einstein in Prague", at Charles University, Prague, June 25-29 ...
Lars Andersson, Andersson, L.
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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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COSMOLOGICAL MODEL SELECTION [PDF]
International Journal of Modern Physics A, 2008 We give an overview of the recent progress in the field of cosmological model selection. Model selection statistics, such as those based on information theory and on Bayesian statistics are introduced and discussed. In the Bayesian framework, the marginalised model likelihood, or evidence, is the primary model selection statistic.
Mukherjee, Pia, Parkinson, David
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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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The viability of modified gravity theories [PDF]
, 2009 PhDThis thesis studies the viability of classes of modified gravity (MG) theories based on generalisations of the Einstein-Hilbert action. Particular emphasis is given to f(R) theories in both the metric and Palatini formalisms, scalar-tensor theories ...
Uddin, Kotub
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The dynamics of cosmological scenarios inspired by quantum gravity [PDF]
, 2006 PhDIn this thesis we study the dynamics of cosmological scenarios inspired by quantum gravity. Part I investigates novel features of the semi-classical regime of homogeneous and isotropic loop quantum cosmology.
Mulryne, David James
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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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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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COSMOLOGICAL PERTURBATIONS AND THE RUNNING COSMOLOGICAL CONSTANT MODEL [PDF]
International Journal of Modern Physics D, 2012 We study the matter density fluctuations in the running cosmological constant (RCC) model using linear perturbations in the longitudinal gauge. Using this observable, we calculate the growth rate of structures and the matter power spectrum, and compare these results to SDSS data and the available data for linear growth rate.
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An alternative to the cosmological “concordance model” [PDF]
Astronomy & Astrophysics, 2003 Precision measurements of the cosmic microwave background by WMAP are believed to have established a flat $Λ$-dominated universe, seeded by nearly scale-invariant adiabatic primordial fluctuations. However by relaxing the hypothesis that the fluctuation spectrum can be described by a single power law, we demonstrate that an Einstein-de Sitter universe ...
Blanchard, Alain +3 more
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