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相关论文: Structure formation constraints on the Jordan-Bran…

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Using the covariant formalism developed in a companion paper (paper I), we derive observational constraint on the Brans-Dicke model in a flat FLRW universe with cosmological constant and cold dark matter. The CMB observations we use include…

宇宙学与河外天体物理 · 物理学 2014-11-18 Fengquan Wu , Xuelei Chen

By using a Markov Chain Monte Carlo simulation, we investigate cosmological constraints on the ghost dark energy (GDE) model in the framework of the Brans-Dicke (BD) theory. A combination of the latest observational data of the cosmic…

宇宙学与河外天体物理 · 物理学 2014-06-13 Hamzeh Alavirad , Ahmad Sheykhi

The Brans-Dicke (BD) theory is the simplest Scalar-Tensor theory of gravity, which can be considered as a candidate of modified Einstein's theory of general relativity. In this work, we forecast the constraints on BD theory in the CSST…

宇宙学与河外天体物理 · 物理学 2022-05-18 Anda Chen , Yan Gong , Fengquan Wu , Yougang Wang , Xuelei Chen

Based on the new cosmic CMB temperature data from the Planck satellite, the 9 year polarization data from the WMAP, the BAO distance ratio data from the SDSS and 6dF surveys, we place a new constraint on the Brans-Dicke theory. We adopt a…

宇宙学与河外天体物理 · 物理学 2013-11-13 Yi-Chao Li , Feng-Quan Wu , Xuelei Chen

We report strong cosmological constraints on the Brans-Dicke (BD) theory of gravity using Cosmic Microwave Background data from Planck.We consider two types of models. First, the initial condition of the scalar field is fixed to give the…

宇宙学与河外天体物理 · 物理学 2014-07-09 A. Avilez , C. Skordis

We discuss the constraints one can place on cosmological parameters using current cosmic microwave background data. A standard $\chi^2$--minimization over band--power estimates is first presented, followed by a discussion of the more…

天体物理学 · 物理学 2007-05-23 J. G. Bartlett , A. Blanchard , M. Douspis , M. Le Dour

We use current cosmic microwave background data to constrain cosmological parameters. The results are presented as confidence regions in the ($\Omega$--$H_o$) -- plane for both open and flat geometries, and are based on a $\chi^2$…

天体物理学 · 物理学 2007-05-23 J. G. Bartlett , A. Blanchard , M. Le Dour , M. Douspis , D. Barbosa

We consider a scalar field interaction with a cosmic string configuration in a flat 3-brane. The origin of this field is given by a compactification mechanism in the context of a 5-dimensional Brans-Dicke theory. We use the Cosmic Microwave…

高能物理 - 理论 · 物理学 2010-04-06 V. B. Bezerra , C. N. Ferreira , G. de A. Marques

We present the results of analysis of constraints on cosmological parameters from cosmic microwave background (CMB) alone and in combination with galaxy cluster baryon fraction assuming inflation--generated adiabatic scalar fluctuations.…

天体物理学 · 物理学 2009-11-06 M. Douspis , A. Blanchard , R. Sadat , J. G. Bartlett , M. Le Dour

We consider the quantum gravity and cosmology of a Jordan-Brans-Dicke theory, predicted by string effective actions. We study its canonical formalism and find that the constraint algebra is that of general relativity, as a consequence of…

广义相对论与量子宇宙学 · 物理学 2009-10-22 Luis J. Garay , Juan Garcia-Bellido

We have reanalysed constraints on the equation of state parameter, w_Q = P/rho, of the dark energy, using several cosmological data sets and relaxing the usual constraint w_Q > -1. We find that combining Cosmic Microwave Background, large…

天体物理学 · 物理学 2009-11-07 Steen Hannestad , Edvard Mortsell

We combine new Cosmic Microwave Background (CMB) data from Planck with Baryon Acoustic Oscillation (BAO) data to constrain the Brans-Dicke (BD) theory, in which the gravitational constant $G$ evolves with time. Observations of type Ia…

宇宙学与河外天体物理 · 物理学 2017-05-19 Ji-Xia Li , Feng-Quan Wu , Yi-Chao Li , Yan Gong , Xue-Lei Chen

In this paper first we study Brans-Dicke equations with the cosmological constant to find an exact solution in the spatially flat Robertson-Walker metric. Then we use Observational Hubble data, the baryon acoustic oscillation distance ratio…

广义相对论与量子宇宙学 · 物理学 2020-08-26 Hassan Amirhashchi , Anil Kumar Yadav

Brans-Dicke (BD), one of the first proposed scalar-tensor theories of gravity, effectively makes the gravitational constant of general relativity (GR) time-dependent. Constraints on the BD parameter $\omega$ serve as a benchmark for testing…

宇宙学与河外天体物理 · 物理学 2024-09-04 Herman Sletmoen , Hans A. Winther

We present a Bayesian approach to combine $Planck$ data and the X-ray physical properties of the intracluster medium in the virialization region of a sample of 320 galaxy clusters ($0.056<z<1.24$, $kT>3$ keV) observed with $Chandra$. We…

宇宙学与河外天体物理 · 物理学 2016-03-09 Andrea Morandi , Ming Sun

We consider higher-dimensional massive Brans-Dicke theory with Ricci-flat internal space. The background model is perturbed by a massive gravitating source which is pressureless in the external (our space) but has an arbitrary…

广义相对论与量子宇宙学 · 物理学 2020-01-03 Ozgur Akarsu , Alexey Chopovsky , Valerii Shulga , Ezgi Yalcinkaya , Alexander Zhuk

We present the first $\Lambda$CDM cosmological analysis performed on a galaxy survey using marked power spectra. The marked power spectrum is the two-point function of a marked field, where galaxies are weighted by a function that depends…

The cosmic curvature density parameter has been constrained in the present work independent of any background cosmological model. The reconstruction is performed adopting the non-parametric Gaussian Processes (GP). The constraints on…

宇宙学与河外天体物理 · 物理学 2022-03-18 Purba Mukherjee , Narayan Banerjee

Many approaches to obtaining cosmological constraints rely on the connection between galaxies and dark matter. However, the distribution of galaxies is dependent on their formation and evolution as well as the cosmological model, and galaxy…

宇宙学与河外天体物理 · 物理学 2014-03-05 Rachel Reddick , Jeremy Tinker , Risa Wechsler , Yu Lu

We place tight constraints on the main cosmological parameters of spatially flat cosmological models by using the recent angular clustering results of XMM-{\it Newton} soft (0.5-2 keV) X-ray sources (Ebrero et al. 2009a), which have a…

宇宙学与河外天体物理 · 物理学 2015-05-14 Spyros Basilakos , Manolis Plionis
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