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Related papers: Growth Index in the $\gamma\delta$CDM model

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The inflessence model has recently been proposed in an attempt to explain both early inflation and present day accelerated expansion within a single mechanism. The model has been successfully tested against the Hubble diagram of Type Ia…

Astrophysics · Physics 2008-11-26 A. A. Sen , V. F. Cardone , S. Capozziello , A. Troisi

An approach to cosmological modelling is presented that incorporates the inhomogeneous structure of the Cosmic Web, specifically focusing on the interplay between cosmic voids and density walls. We extend the standard homogeneous and…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-12 John Moffat

The growth of matter perturbations in the $f(R)$ model proposed by Starobinsky is studied in this paper. Three different parametric forms of the growth index are considered respectively and constraints on the model are obtained at both the…

General Relativity and Quantum Cosmology · Physics 2011-01-05 Xiangyun Fu , Puxun Wu , Hongwei Yu

Cosmologies including continuous matter creation are able to reproduce the main properties of the standard $\Lambda$CDM model, in particular in cases where the particle and entropy production rates are equal. These specific models,…

General Relativity and Quantum Cosmology · Physics 2011-03-07 Alain de Roany , J. A. de Freitas Pacheco

The parameter $\sigma_8$ is the rms mass fluctuations on a scale of $R_8=8h^{-1}$ Mpc and is used to quantify the amplitude of matter fluctuations at linear scales. However, the dependence of $R_8$ on $h$ complicates direct comparisons of…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-18 Matteo Forconi , Arianna Favale , Adrià Gómez-Valent

The standard $\Lambda$CDM cosmological model informed by cosmic microwave background (CMB) anisotropies makes a precise prediction for the growth of matter density fluctuations over cosmic time on linear scales. A variety of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-14 Mathew S. Madhavacheril

The $S_8$ value inferred from the Subaru Hyper Suprime-Cam (HSC) Year 3 cosmic shear data, under the assumption of the flat $\Lambda$CDM model, is 2-3$\sigma$ lower than that inferred from observations of the early-time universe, such as…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-15 Ryo Terasawa , Masahiro Takada , Toshiki Kurita , Sunao Sugiyama

The next generation of space-based galaxy surveys are expected to measure the growth rate of structure to about a percent level over a range of redshifts. The rate of growth of structure as a function of redshift depends on the behaviour of…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Anatoly Pavlov , Lado Samushia , Bharat Ratra

The current standard cosmological model is constructed within the framework of general relativity with a cosmological constant $\Lambda$, which is often associated with dark energy, and phenomenologically explains the accelerated cosmic…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Jiamin Hou , Julian Bautista , Maria Berti , Carolina Cuesta-Lazaro , César Hernández-Aguayo , Tilman Tröster , Jinglan Zheng

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

The cosmic expansion history tests the dynamics of the global evolution of the universe and its energy density contents, while the cosmic growth history tests the evolution of the inhomogeneous part of the energy density. Precision…

Astrophysics · Physics 2008-11-26 Eric V. Linder

Among various phenomenological $\Lambda$ models, a time-dependent model $\dot \Lambda\sim H^3$ is selected here to investigate the $\Lambda$-CDM cosmology. Using this model the expressions for the time-dependent equation of state parameter…

General Relativity and Quantum Cosmology · Physics 2011-01-25 Saibal Ray , Maxim Khlopov , Utpal Mukhopadhyay , Partha Pratim Ghosh

We present constraints on the cosmic growth history with recent cosmological data, allowing for deviations from Lambda CDM as might arise if cosmic acceleration is due to modifications to GR or inhomogeneous dark energy. We combine measures…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-12 Rachel Bean , Matipon Tangmatitham

The Hubble constant ($H_0$), which represents the expansion rate of the Universe, is one of the most important cosmological parameters. The recent measurements of $H_0$ using the distance ladder methods such as Type Ia Supernovae (SNe Ia)…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-14 Rahul Kumar Thakur , Shashikant Gupta , Rahul Nigam , PK Thiruvikraman

We investigate the impact of a non-gravitational interaction between dark matter and dark energy on the growth rate of matter density perturbations within the framework of a $w$CDM scenario, where the coupling is proportional to the dark…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-06 Fan Yang , Rongrong Zhai , Xiangyun Fu , Bing Xu , Kaiwen Liu , Chikun Ding , Yang Huang

We performed a Bayesian study on three beyond LCDM phenomenological triggering parameters, the growth index $\gamma$, the dark energy equation of state parameter $w$ and the lensing deviation from the GR prediction parameter $\Sigma$, using…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-06 Ziad Sakr

We perform N-body simulations for $f(T)$ gravity using the ME-Gadget code, in order to investigate for the first time the structure formation process in detail. Focusing on the power-law model, and considering the model-parameter to be…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Yiqi Huang , Jiajun Zhang , Xin Ren , Emmanuel N. Saridakis , Yi-Fu Cai

We have put forward a new unified framework which provides a consistent and rather complete account of the growth index of matter perturbations in the regime where the dark energy is allowed to have clustering. In particular, we find that…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Spyros Basilakos

Beyond testing the current cosmological paradigm, cluster number counts can also be utilized to investigate the discrepancies currently affecting current cosmological measurements. In particular, cosmological studies based on cosmic shear…

We study models of late-time cosmic acceleration in terms of scalar-tensor theories generalized to include a certain class of non-linear derivative interaction of the scalar field. The non-linear effect suppress the scalar-mediated force at…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Tsutomu Kobayashi