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Systematic Dynamical Analysis in Palatini f(R) Gravity
Advances in Astronomy, Volume 2024, Issue 1, 2024.This paper aims to explore the evolution of the universe in the background of Palatini f(R) gravity. Considering Amendola Gannouji Polarski Tsujikawa (AGPT) f(R) gravity model, we perform a dynamical system analysis within the FLRW universe in order to analyze the impacts of this gravity model on large‐scale structure and dynamics of universe. With the
Fizza Saeed +3 more
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Elements of cosmology beyond FLRW
SciPost Physics Lecture NotesModern cosmology is based on the cosmological principle, which states that the Universe is statistically homogeneous and isotropic. When applied in its strict – rather than statistical – sense, the cosmological principle leads to the Friedmann–Lemaître ...
Pierre Fleury
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Correspondence between dark energy quantum cosmology and Maxwell equations
European Physical Journal C: Particles and Fields, 2019 A Friedmann–Robertson–Walker cosmology with dark energy can be modelled using a quintessence field. That system is equivalent to a relativistic particle moving on a two-dimensional conformal spacetime.
Felipe A. Asenjo, Sergio A. Hojman
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Generalized holographic cosmology: low-redshift observational constraint
Journal of High Energy Physics, 2021 Four-dimensional cosmological models are studied on a boundary of a five-dimensional Anti-de Sitter (AdS 5) black hole with AdS Reissner-Nordström and scalar charged Reissner-Nordström black hole solutions, where we call the former a “Hairless” black ...
Sunly Khimphun +2 more
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Acta Physica Polonica B, 2016 We construct and investigate the general stress-energy tensor, Tb a, of the quantized massive field in the D-dimensional spatially-flat Friedmann- Robertson-Walker spacetime within the framework of the adiabatic approximation. The behavior of Tb a for 4 D 12 is examined for the exponential (in the conformal time) and power-law cosmological models with ...
Jerzy Andrzej Matyjasek, Tryniecki, D.
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Analyzing cosmic inhomogeneities through perturbative modifications of FLRW spacetime
European Physical Journal C: Particles and FieldsThis research study investigates the modification of Friedmann–Lemaitre–Robertson–Walker (FLRW) spacetime, emphasizing the effects of universe expansion, dark matter, and cosmological perturbations.
Mutahir Ali, Farhad Ali
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Complex Riemannian Spacetime and Singularity-Free Black Holes and Cosmology
AxiomsAn approach is presented to address singularities in general relativity using a complex Riemannian spacetime extension. We demonstrate how this method can be applied to both black hole and cosmological singularities, specifically focusing on the ...
John W. Moffat
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McVittie–Plummer Spacetime: Plummer Sphere Immersed in the FLRW Universe
The Astrophysical JournalThe McVittie–Plummer spacetime is a spherically symmetric inhomogeneous cosmological model that represents a spherical star system embedded in a standard Friedmann–Lemaître–Robertson–Walker (FLRW) cosmological model. We study the main physical properties
Javad Tabatabaei +2 more
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, 2019 In this paper we investigate the quantum Brownian motion of a massive scalar point particle induced by the FRW spacetime in the presence of a linear topological defect named cosmic string. In addition, we also consider a flat boundary orthogonal to the defect to analyse its effect on the particle's motion.
Mota, Herondy F. Santana +1 more
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Gravitational Entropy and the Second Law of Thermodynamics
Entropy, 2015 The spontaneous violation of Lorentz and diffeomorphism invariance in a phase near the big bang lowers the entropy, allowing for an arrow of time and the second law of thermodynamics. The spontaneous symmetry breaking leads to
John W. Moffat
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