Results 21 to 30 of about 6,695,532 (296)
Collapse Models and Cosmology [PDF]
, 2020 minor typo in equation (30) corrected, conclusions and results ...
Martin, Jérôme, Vennin, Vincent
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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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Applications of cosmological perturbation theory [PDF]
, 2011 PhDCosmological perturbation theory is crucial for our understanding of the universe. The linear theory has been well understood for some time, however developing and applying the theory beyond linear order is currently at the forefront of research in
Christopherson, Adam J.
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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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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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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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FLRW Cosmological Models with Dynamic Cosmological Term in Modified Gravity
Universe, 2021 Although the standard lambda cold dark matter cosmological model is quite successful in describing the universe, there are still several issues that are still not resolved.
Rishi Kumar Tiwari +2 more
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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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Crossing of Phantom Divide Line in Model of Interacting Tsallis Holographic Dark Energy
Universe, 2022 We consider a Tsallis holographic dark energy model with interaction between dark energy and matter. The density of dark energy is taken as ρd∼3C2/L4−2γ, where C, γ are constants. The event horizon is chosen as the characteristic scale L.
Artyom V. Astashenok +1 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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