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We take into account redshift-space distortion measurements to investigate the growth of cosmological large-scale structures within the framework of modified symmetric teleparallel $f(Q)$ gravity. After comparing the predictions of the…

General Relativity and Quantum Cosmology · Physics 2025-03-20 Shambel Sahlu , Álvaro de la Cruz-Dombriz , Amare Abebe

The treatment of 1 + 3 covariant perturbation in a multifluid cosmology with the consideration of f (G) gravity, G being the Gauss-Bonnet term, is done in the present paper. We define a set of covariant and gauge-invariant variables to…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Albert Munyeshyaka , Abraham Ayirwanda , Fidele Twagirayezu , Joseph Ntahompagaze

Future galaxy surveys hope to distinguish between the dark energy and modified gravity scenarios for the accelerating expansion of the Universe using the distortion of clustering in redshift space. The aim is to model the form and size of…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-06 Elise Jennings , Carlton M. Baugh , Silvia Pascoli

In this paper, we consider a gravitational action containing a combination of the Ricci scalar, $R$, and the topological Gauss--Bonnet term, $G$. Specifically, we study the cosmological features of a particular class of modified gravity…

General Relativity and Quantum Cosmology · Physics 2023-03-15 Francesco Bajardi , Rocco D'Agostino

This study is devoted to the implications of scale-dependent gravity in Cosmology. Redshift-space distortion data indicate that there is a tension between $\Lambda$CDM and available observations as far as the value of the rms density…

General Relativity and Quantum Cosmology · Physics 2021-06-08 Grigoris Panotopoulos , Ángel Rincón

We explore cosmological perturbations in a modified Gauss-Bonnet f(G) gravity, using a 1+3 covariant formalism. In such a formalism, we define gradient variables to get perturbed linear evolution equations. We transform these linear…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Albert Munyeshyaka , Joseph Ntahompagaze , Tom Mutabazi

Cosmic growth of large scale structure probes the entire history of cosmic expansion and gravitational coupling. To get a clear picture of the effects of modification of gravity we consider a deviation in the coupling strength (effective…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-19 Mikhail Denissenya , Eric V. Linder

In this work, we present a method for numerically solving the Friedmann equations of modified $f(\mathcal{G})$ gravity in the presence of pressureless matter. This method enables us to predict the redshift behaviour of the Hubble expansion…

General Relativity and Quantum Cosmology · Physics 2024-11-08 Santosh V. Lohakare , Soumyadip Niyogi , B. Mishra

Cosmology faces a pressing challenge with the Hubble constant ($H_0$) tension, where the locally measured rate of the Universe's expansion does not align with predictions from the cosmic microwave background (CMB) calibrated with…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-27 Rebecca Briffa , Celia Escamilla-Rivera , Jackson Levi Said , Jurgen Mifsud

Redshift space distortions caused by galaxy peculiar velocities provide a window onto the growth rate of large scale structure and a method for testing general relativity. We investigate through a comparison of N-body simulations to various…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Juliana Kwan , Geraint F. Lewis , Eric V. Linder

We compile a list of $14$ independent measurements of large-scale structure growth rate between redshifts $0.067 \leq z \leq 0.8$ and use this to place constraints on model parameters of constant and time-evolving general-relativistic dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Anatoly Pavlov , Omer Farooq , Bharat Ratra

We use baryon acoustic oscillation and redshift space distortion from the completed Baryon Oscillation Spectroscopic Survey, corresponding to data release 12 of the Sloan Digital Sky Survey, combined sample analysis in combination with…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-09 Eva-Maria Mueller , Will Percival , Eric Linder , Shadab Alam , Gong-Bo Zhao , Ariel G. Sánchez , Florian Beutler

We present a new model for the cross-covariance between galaxy redshift-space distortions and peculiar velocities. We combine this with the auto-covariance models of both probes in a fully self-consistent, maximum-likelihood method,…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Caitlin Adams , Chris Blake

We investigate the evolution of cosmic structures within the framework of modified gravity, specifically focusing on theories described by the function $f(R, L_m)$, where $R$ is the Ricci scalar and $L_m$ is the matter Lagrangian. This…

General Relativity and Quantum Cosmology · Physics 2025-07-08 G. K. Goswami , J. P. Saini

Adding to our previous method for dealing with gravitational modifications at redshift $z\gtrsim3$ through a single parameter, we investigate treatment of lower redshift modifications to linear growth observables. We establish subpercent…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-29 Mikhail Denissenya , Eric V. Linder

We investigate cosmological perturbations of f(G) gravity in the presence of a scalar field. Using the 1 + 3 covariant formalism, we present the energy overdensity perturbation equations responsible for large scale structure formation.…

General Relativity and Quantum Cosmology · Physics 2023-12-27 Albert Munyeshyaka , Joseph Ntahompagaze , Tom Mutabazi , Manasse. R Mbonye

The key probes of the growth of large-scale structure are its rate $f$ and amplitude $\sigma_8$. Redshift space distortions in the galaxy power spectrum allow us to measure only the combination $f\sigma_8$, which can be used to constrain…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Louis Perenon , Stéphane Ilić , Roy Maartens , Alvaro de la Cruz-Dombriz

Using redshift space distortion data, we perform model-independent reconstructions of the growth history of matter inhomogeneity in the expanding Universe using two methods: crossing statistics and Gaussian processes. We then reconstruct…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-08 Benjamin L'Huillier , Arman Shafieloo , David Polarski , Alexei A. Starobinsky

Observations of redshift-space distortions in spectroscopic galaxy surveys offer an attractive method for observing the build-up of cosmological structure, which depends both on the expansion rate of the Universe and our theory of gravity.…

Astrophysics · Physics 2010-04-22 Martin White , Yong-Seon Song , Will J. Percival

Ongoing and future redshift surveys have the capability to measure the growth rate of large scale structure at the percent level over a broad range of redshifts, tightly constraining cosmological parameters. Beyond general relativity,…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-17 Mikhail Denissenya , Eric V. Linder
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