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Related papers: Cosmological constraints on viable $f(R)$ models u…

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The main aim of this paper is to provide cosmological constraints on the Multi Scalar Field Dark Matter model (MSFDM), in which we assume the dark matter is made up of different ultra-light scalar fields. As a first approximation, we…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-05 L. O. Téllez-Tovar , Tonatiuh Matos , J. Alberto Vázquez

We review current observations of the homogeneous cosmological expansion which, because they measure only kinematic variables, cannot determine the dynamics driving the recent accelerated expansion. The minimal fit to the data, the flat…

Astrophysics · Physics 2015-05-13 Sidney Bludman

We consider cosmological modelling in $f(R)$ theories of gravity, using both top-down and bottom-up constructions. The top-down models are based on Robertson-Walker geometries, and the bottom-up constructions are built by patching together…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Timothy Clifton , Peter K. S. Dunsby

Accelerating expansion of the Universe is a great challenge for both physics and cosmology. In light of lacking the convincing theoretical explanation, an effective description of this phenomenon in terms of cosmic equation of state turns…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 M. Biesiada , A. Piorkowska , B. Malec

Gravitational lenses can provide crucial information on the geometry of the Universe, on the cosmological scenario of formation of its structures as well as on the history of its components with look-back time. In this review, I focus on…

Astrophysics · Physics 2009-10-31 Y. Mellier

In this Thesis I discuss several recent results obtained using the CMB spectra measured by Planck and several other cosmological probes. Extensions of the $\Lambda$CDM model are studied, including the presence of an additional sterile…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-31 Stefano Gariazzo

Inspired by an exponential $f(R)$ gravity model studied in the literature, in this work we introduce a new and viable $f(Q)$ gravity model, which can be represented as a perturbation of $\Lambda$CDM. Typically, within the realm of $f(Q)$…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-31 A. Oliveros , Mario A. Acero

The standard cosmological model is based on general relativity and includes dark matter and dark energy. An important prediction of this model is a fixed relationship between the gravitational potentials responsible for gravitational…

Astrophysics · Physics 2008-11-26 Pengjie Zhang , Michele Liguori , Rachel Bean , Scott Dodelson

We examine the constraints that can be obtained on standard cold dark matter models from the most currently used data set: CMB anisotropies, type Ia supernovae and the SDSS luminous red galaxies. We also examine how these constraints are…

Astrophysics · Physics 2015-05-13 L. D. Ferramacho , A. Blanchard , Y. Zolnierowski

This chapter provides a comprehensive overview of weak gravitational lensing and its current applications in cosmology. We begin by introducing the fundamental concepts of gravitational lensing and derive the key equations for the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-06 J. Prat , D. Bacon

We present the current status of cosmic shear studies and their implications on cosmological models. Theoretical expectations and observational results are discussed in the framework of standard cosmology and CDM scenarios. The potentials…

Astrophysics · Physics 2009-11-07 Y. Mellier , L. van Waerbeke , F. Bernardeau , I. Tereno

We revisit a weak gravitational lensing problem by constructing a setup which describes the actual system as accurately as possible and solving the null geodesic equations. Details are given for the case of a Universe driven only by a…

Astrophysics · Physics 2008-11-26 Minjoon Park

Since viable $f(R)$ gravity models must reconcile early-universe inflation with late-time acceleration, we specifically study the dynamical behavior of such a theory during the matter-dominated to dark-energy-dominated transition epoch. By…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-03 Siqi He , Weiqiang Yang , Hangyi Jin

Dark energy may be the first sign of new fundamental physics in the Universe, taking either a physical form or revealing a correction to Einsteinian gravity. Weak gravitational lensing and galaxy peculiar velocities provide complementary…

We study the evolution of linear cosmological perturbations in f(R) models of accelerated expansion in the physical frame where the gravitational dynamics are fourth order and the matter is minimally coupled. These models predict a rich and…

Astrophysics · Physics 2008-11-26 Yong-Seon Song , Wayne Hu , Ignacy Sawicki

A class of well-behaved modified gravity models with long enough matter domination epoch and a late-time accelerated expansion is confronted with SNIa, CMB, SDSS, BAO and H(z) galaxy ages data, as well as current measurements of the linear…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-09 Z. Girones , A. Marchetti , O. Mena , C. Pena-Garay , N. Rius

We compute the constraints on a ``standard'' 10 parameter cold dark matter (CDM) model from the most recent CMB and data and other observations, exploring 30 million discrete models and two continuous parameters. Our parameters are the…

Astrophysics · Physics 2009-09-25 Max Tegmark , Matias Zaldarriaga

We perform multi-plane ray-tracing using the GLAMER gravitational lensing code within high-resolution light-cones extracted from the CoDECS simulations: a suite of cosmological runs featuring a coupling between Dark Energy and Cold Dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Carlo Giocoli , R. Benton Metcalf , Marco Baldi , Massimo Meneghetti , Lauro Moscardini , Margarita Petkova

The nature of dark matter is increasingly constrained by cosmological data. In this paper, we examine the implications of the Cosmic Microwave Background anisotropy limits on the density of cold dark matter under different theoretical…

Astrophysics · Physics 2009-11-07 A. Melchiorri , J. Silk

The lensing convergence field describing the weak lensing effect of the Cosmic Microwave Background (CMB) radiation is expected to be subject to mild deviations from Gaussianity. We perform a suite of full-sky lensing simulations using ray…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-18 Jan Hamann , Yuqi Kang