Search Results - "Sakr, Ziad"

Untying the Growth Index to Relieve the σ8 Discomfort by Sakr, Ziad

“…The matter fluctuation parameter σ8 is, by model construction, degenerate with the growth index γ. Here, we study the effect on the cosmological parameter…”
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A Short Review on the Latest Neutrinos Mass and Number Constraints from Cosmological Observables by Sakr, Ziad

“…We review the neutrino science, focusing on its impact on cosmology along with the latest constraints on its mass and number of species. We also discuss its…”
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The Copernican principle in light of the latest cosmological data by Camarena, David, Marra, Valerio, Sakr, Ziad, Clarkson, Chris

“…ABSTRACT We pursue a program to confront observations with inhomogeneous extensions of the FLRW metric. The main idea is to test the Copernican principle (CP)…”
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Untying the Growth Index to Relieve the Iσ/I[sub.8] Discomfort by Sakr, Ziad

“…The matter fluctuation parameter σ[sub.8] is, by model construction, degenerate with the growth index γ. Here, we study the effect on the cosmological…”
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Testing the cosmological Poisson equation in a model-independent way by Zheng, Ziyang, Sakr, Ziad, Amendola, Luca

“…We show how one can test the cosmological Poisson equation by requiring only the validity of three main assumptions: the energy-momentum conservation equations…”
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A trium test on beyond $\Lambda$CDM triggering parameters by Sakr, Ziad

“…We performed a Bayesian study on three beyond LCDM phenomenological triggering parameters, the growth index $\gamma$, the dark energy equation of state…”
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Testing the hypothesis of a matter density discrepancy within LCDM model using multiple probes by Sakr, Ziad

“…We investigate whether the two cosmological discrepancies on the Hubble constant ($H_0$) and the matter fluctuation parameter ($\sigma_8$) are suggesting and…”
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Extensions to $\Lambda$CDM at Intermediate Redshifts to Solve the Tensions ? by Sakr, Ziad

“…Models of dark energy or modified gravity that tries to alleviate the tensions on the Hubble constant ($H_0$) and the matter fluctuation parameter ($\sigma_8$)…”
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Untying the growth index to relieve the $\sigma_8$ discomfort by Sakr, Ziad

“…The matter fluctuation parameter $\sigma_8$ is, by model construction, degenerate with the growth index $\gamma$. Here, we study the effect on the cosmological…”
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Investigating the Hubble Tension and $\sigma_8$ Discrepancy in f(Q) Cosmology by Sakr, Ziad, Schey, Leonid

“…In this study, we incorporated a three-parameter family, of the metric incompatible modification of standard general relativity $f(Q)$ models into the…”
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Gravitation and the Universe from large scale-structures: The GAUSS mission concept Mapping the cosmic web up to the reionization era by Blanchard, Alain, Aubourg, Éric, Brax, Philippe, Castander, Francisco J., Codis, Sandrine, Escoffier, Stéphanie, Dournac, Fabien, Ferté, Agnès, Finelli, Fabio, Fosalba, Pablo, Gangler, Emmanuel, Gontcho, Satya Gontcho A, Hawken, Adam, Ilić, Stéphane, Kneib, Jean-Paul, Kunz, Martin, Lavaux, Guilhem, Le Fèvre, Olivier, Lesgourgues, Julien, Mellier, Yannick, Neveu, Jérémy, Rasera, Yann, Renault, Cécile, Ricci, Marina, Sakr, Ziad, Sanchez, Norma G., Tutusaus, Isaac, Yahia-Cherif, Safir

“…Today, thanks in particular to the results of the ESA Planck mission, the concordance cosmological model appears to be the most robust to describe the…”
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Cosmological Constraints on sub-horizon scales modified gravity theories with MGCLASS II by Sakr, Ziad, Martinelli, Matteo

“…In this paper we introduce a new public Einstein-Boltzmann solver, \texttt{MGCLASS II}, built as a modification to the publicly available \texttt{CLASS} code,…”
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Can varying the gravitational constant alleviate the tensions ? by Sakr, Ziad, Sapone, Domenico

“…Constraints on the cosmological concordance model parameters from observables at different redshifts are usually obtained using the locally measured value of…”
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Gravitation and the Universe from large scale-structures by Blanchard, Alain, Aubourg Éric, Brax Philippe, Castander, Francisco J, Codis Sandrine, Escoffier Stéphanie, Dournac Fabien, Ferté Agnès, Finelli Fabio, Fosalba Pablo, Gangler Emmanuel, Gontcho Satya Gontcho A, Hawken, Adam, Ilić Stéphane, Jean-Paul, Kneib, Kunz, Martin, Lavaux Guilhem, Le Fèvre Olivier, Lesgourgues Julien, Mellier Yannick, Neveu Jérémy, Rasera Yann, Renault Cécile, Ricci, Marina, Sakr Ziad, Sanchez, Norma G, Tutusaus Isaac, Yahia-Cherif Safir

“…Today, thanks in particular to the results of the ESA Planck mission, the concordance cosmological model appears to be the most robust to describe the…”
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Testing the cosmological Poisson equation in a model-independent way by Zheng, Ziyang, Sakr, Ziad, Amendola, Luca

“…We show how one can test the cosmological Poisson equation by requiring only the validity of three main assumptions: the energy-momentum conservation equations…”
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The distribution of Bayes' ratio by Amendola, Luca, Patel, Vrund, Sakr, Ziad, Sellentin, Elena, Wolz, Kevin

“…The ratio of Bayesian evidences is a popular tool in cosmology to compare different models. There are however several issues with this method: Bayes' ratio…”
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Cluster counts III. $\Lambda$CDM extensions and the cluster tension by Sakr, Ziad, Ilic, Stephane, Blanchard, Alain

“…A&A 666, A34 (2022) In this work, we examine whether further extensions to the $\Lambda$CDM model could alleviate the $\sigma_8$ tension. For that, we derive…”
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A void in the Hubble tension? The end of the line for the Hubble bubble by Camarena, David, Marra, Valerio, Sakr, Ziad, Clarkson, Chris

“…Class. Quantum Grav. 39 184001 (2022) The Universe may feature large-scale inhomogeneities beyond the standard paradigm, implying that statistical homogeneity…”
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Testing General Relativity from Curvature & Energy contents at Cosmological scale by Sakr, Ziad, Blanchard, Alain

“…In this work we examine what are the cosmological implications of allowing the geometrical curvature density to behave independently from the energy density…”
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The Copernican principle in light of the latest cosmological data by Camarena, David, Marra, Valerio, Sakr, Ziad, Clarkson, Chris

“…MNRAS 509 (1), 1291-1302 (2022) We pursue a program to confront observations with inhomogeneous extensions of the FLRW metric. The main idea is to test the…”
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