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Related papers: Exploring the Growth-Index ($\gamma$) Tension with…

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We present a new measurement of structure growth at $z \simeq 0.08$ obtained by correlating the cosmic microwave background (CMB) lensing potential map from the \textit{Planck} satellite with the angular distribution of the 2MASS…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-08 Federico Bianchini , Christian L. Reichardt

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 perform a validation of estimates of the growth rate of structure, described by the parameter combination $f\sigma_8$, in modified gravity cosmologies. We consider an analysis pipeline based on the redshift-space distortion modelling of…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-08 Alexandre Barreira , Ariel G. Sánchez , Fabian Schmidt

The standard model of cosmology, the $\Lambda$CDM model, describes the evolution of the Universe since the Big Bang with just a few parameters, six in its basic form. Despite being the simplest model, direct late-time measurements of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-17 Lavinia Heisenberg , Hector Villarrubia-Rojo

A recent determination of the growth index indicates a value significantly higher than the $\Lambda$CDM prediction, suggesting that alternative scenarios to $\Lambda$CDM may be required. In this work, we investigate whether a time-varying…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Ícaro. B. S. Cortês , Léo. G. Medeiros , Ronaldo C. Batista

We use measurements of the growth of cosmic structure, as inferred from the observed evolution of the X-ray luminosity function (XLF) of galaxy clusters, to constrain departures from General Relativity (GR) on cosmological scales. We employ…

Astrophysics · Physics 2015-05-13 David Rapetti , Steven W. Allen , Adam Mantz , Harald Ebeling

We use measurements from the Planck satellite mission and galaxy redshift surveys over the last decade to test three of the basic assumptions of the standard model of cosmology, $\Lambda$CDM: the spatial curvature of the universe, the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 Shadab Alam , Shirley Ho , Alessandra Silvestri

Perhaps the deepest mystery of our accelerating Universe in expansion is the existence of a tiny and rigid cosmological constant, $\Lambda$. Its size is many orders of magnitude below the expected one in the standard model of particle…

General Relativity and Quantum Cosmology · Physics 2015-04-03 Joan Sola , Adria Gomez-Valent

Several cosmological tensions have emerged in light of recent data, most notably in the inferences of the parameters $H_0$ and $\sigma_8$. We explore the possibility of alleviating both these tensions {\it simultaneously} by means of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-29 Arsalan Adil , Andreas Albrecht , Lloyd Knox

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

The excellent measurements of the cosmic microwave background (CMB) fluctuations by Planck allow us to tightly constrain the amplitude of matter fluctuations at redshift $\sim 1100$ in the $\Lambda$-cold dark matter ($\Lambda$CDM) model.…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-21 Alain Blanchard , Stéphane Ilić

Yes, for a wide range of cosmological models ($\Lambda$CDM, non-interacting $w_z$CDM or models with possible interactions between dark energy and dark matter, in either phantom or non-phantom regimes). In the recent past there have been…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-17 Archita Bhattacharyya , Ujjaini Alam , Kanhaiya Lal Pandey , Subinoy Das , Supratik Pal

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

[abridged] The $\eta$CDM framework is a new cosmological model aimed to cure some drawbacks of the standard $\Lambda$CDM scenario, such as the origin of the accelerated expansion at late times, the cosmic tensions, and the violation of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-11 Andrea Lapi , Balakrishna S. Haridasu , Lumen Boco , Marcos M. Cueli , Carlo Baccigalupi , Luigi Danese

We propose a cosmological model, \"u$\Lambda$CDM, based on {\it \"uber-gravity}, which is a canonical ensemble average of many theories of gravity. In this model, we have a sharp transition from (a purely) $\Lambda$CDM era to a phase in…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-22 Nima Khosravi , Shant Baghram , Niayesh Afshordi , Natacha Altamirano

The concordance (LambdaCDM) model reproduces the main current cosmological observations assuming the validity of general relativity at all scales and epochs, the presence of cold dark matter, and of a cosmological constant, equivalent to a…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-08 Guido Risaliti , Elisabeta Lusso

A well-known problem of the $\Lambda$CDM model is the tension between the relatively high level of clustering, as quantified by the parameter $\sigma_8$, found in cosmic microwave background experiments and the smaller one obtained from…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-04 Bruno J. Barros , Luca Amendola , Tiago Barreiro , Nelson J. Nunes

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

It is found that a non-minimally coupled scalar tensor theory, Thawing Gravity (TG), can explain multiple tensions plaguing the standard cosmological model $\Lambda$CDM while fitting better to observations than the latter. Using the…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-06 Gen Ye

We infer the growth of large scale structure over the redshift range $0.4\lesssim z \lesssim 1$ from the cross-correlation of spectroscopically calibrated Luminous Red Galaxies (LRGs) selected from the Dark Energy Spectroscopic Instrument…

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