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Assuming a spatially flat universe, we study the cosmological viability of an infrared corrected teleparallel gravity model, which accounts for late acceleration by weakening gravity at later times on cosmological distances. The theory does…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Mahmoud Hashim , Waleed El Hanafy , Alexey Golovnev , Amr A. El-Zant

In this paper, we present a kinematic analysis of the Universe's expansion history using cosmography, with a particular emphasis on the jerk parameter $j_0$, which is equal to one in the standard $\Lambda$CDM scenario. We use distance…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-02 Gabriel Rodrigues , Rayff de Souza , Jailson Alcaniz

Recently, spatially inhomogeneous cosmological models have been proposed as an alternative to the LCDM model, with the aim of reproducing the late time dynamics of the Universe without introducing a cosmological constant or dark energy.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Peter Dunsby , Naureen Goheer , Bob Osano , Jean-Philippe Uzan

Recent observations of high-redshift Type Ia supernovae have placed stringent constraints on the cosmological constant $\Lambda$. We explore the implications of these SNe observations for cosmological models in which a classically evolving…

Astrophysics · Physics 2009-10-30 Joshua A. Frieman , Ioav Waga

The power spectrum of mass density fluctuations is evaluated from the Mark III and the SFI catalogs of peculiar velocities by a maximum likelihood analysis, using parametric models for the power spectrum and for the errors. The applications…

Astrophysics · Physics 2007-05-23 Idit Zehavi , Avishai Dekel

We use higher-redshift gamma-ray burst (GRB), HII starburst galaxy (HIIG), and quasar angular size (QSO-AS) measurements to constrain six spatially flat and non-flat cosmological models. These three sets of cosmological constraints are…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Shulei Cao , Joseph Ryan , Narayan Khadka , Bharat Ratra

We examine the observational viability of a class of $f(\mathcal{R})$ gravity cosmological models. Particular attention is devoted to constraints from the recent observational determination of the redshift of the cosmological…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Salvatore Capozziello , Omer Farooq , Orlando Luongo , Bharat Ratra

From a phenomenological point of view, we analyze the dynamics of the Universe at late times by introducing a polynomial and hyperbolic bulk viscosity into the Einstein field equations respectively. We constrain their free parameters using…

General Physics · Physics 2019-10-01 A. Hernández-Almada

We consider a varieties of quintessence scalar field models in a homogeneous and isotropic geometry of the universe with zero spatial curvature aiming to provide stringent constraints using a series of cosmological data sets, namely, the…

General Relativity and Quantum Cosmology · Physics 2019-07-24 Weiqiang Yang , M. Shahalam , Barun Pal , Supriya Pan , Anzhong Wang

Deriving the expansion history of the Universe is a major goal of modern cosmology. To date, the most accurate measurements have been obtained with Type Ia Supernovae and Baryon Acoustic Oscillations, providing evidence for the existence of…

We put forward a pressure-parametric model to study the tiny deviation from cosmological constant(CC) behavior of the dark sector accelerating the expansion of the Universe. Data from cosmic microwave background (CMB) anisotropies, baryonic…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-29 Yan-Hong Yao , Xin-He Meng

Cosmic chronometers offer a model-independent way to trace the expansion history of the Universe via the dating of passively evolving objects. This enables testing the validity of cosmological models without concrete assumptions of their…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-05 Carlos A. Álvarez , Marcos M. Cueli , Alessandro Bressan , Lumen Boco , Balakrishna S. Haridasu , Michele Bosi , Luigi Danese , Andrea Lapi

We propose a new theoretical approach for a cosmological model, which starts from an exponential of the trace of the energy-momentum tensor-dependence on the gravitational action, to be summed to the Ricci scalar. We derive the referred…

General Relativity and Quantum Cosmology · Physics 2020-04-08 P. H. R. S. Moraes , P. K. Sahoo , S. K. J. Pacif

The Hubble relation between distance and redshift is a purely cosmographic relation that depends only on the symmetries of a FLRW spacetime, but does not intrinsically make any dynamical assumptions. This suggests that it should be possible…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Matt Visser , Celine Cattoen

Mapping the expansion history of the universe is a compelling task of physical cosmology, especially in the context of the observational evidence for the recent acceleration of the universe, which demonstrates that canonical theories of…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-30 B. A. R. Rocha , C. J. A. P. Martins

The current big-bang cosmological model requires re-introduction of Einstein's "regretted" old cosmological constant to fit the astronomical measurements of supernova Ia magnitude versus redshift. The physical basis of the cosmological…

Astrophysics · Physics 2007-05-23 Charles B. Leffert

The current standard model of cosmology, the LambdaCDM model, is based on the homogeneous FLRW solutions of the Einstein equations to which some perturbations are added to account for the CMB features and structure formation at large…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-14 Marie-Noëlle Célérier

In this manuscript I review the mathematics and physics that underpins recent work using the clustering of galaxies to derive cosmological model constraints. I start by describing the basic concepts, and gradually move on to some of the…

Astrophysics · Physics 2009-07-28 Will J. Percival

In this paper we summarise the constraints that low-redshift data --such as supernovae Ia (SN Ia), baryon acoustic oscillations (BAO) and cosmic chronometers (CC)-- are able to set on the concordance model and its extensions, as well as on…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-29 Vladimir V. Luković , Balakrishna S. Haridasu , Nicola Vittorio

In the paper, we consider two models in which dark energy is coupled with either dust matter or dark matter, and discuss the conditions that allow more time for structure formation to take place at high redshifts. These models are expected…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-08 Shulei Cao , Tong-Jie Zhang , Xinya Wang , Tingting Zhang
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