中文
相关论文

相关论文: Anisotropic massive Brans-Dicke gravity extension …

200 篇论文

We consider the ADM formalism of the Brans-Dicke theory and propose an anisotropic extension of the theory by introducing five free parameters. We find that the resulting theory reveals many interesting aspects which are not present in the…

高能物理 - 理论 · 物理学 2015-06-15 Taeyoon Moon , Phillial Oh

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

The cosmological principle is a cornerstone of the standard cosmological model. However, recent observations suggest potential deviations from this assumption, hinting at a small anisotropic expansion. Such an expansion can arise from…

It has been shown that four dimensional Brans-Dicke theory with effective matter field and self interacting potential can be achieved from vacuum 5D BD field equations, where we refer to as modified Brans-Dicke theory (MBDT). We investigate…

广义相对论与量子宇宙学 · 物理学 2015-05-28 S. M. M. Rasouli , Mehrdad Farhoudi , Hamid R. Sepangi

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 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

Recent studies by Sol\`a Peracaula, G\'omez-Valent, de Cruz P\'erez and Moreno-Pulido (2019,2020) have pointed out the intriguing possibility that Brans-Dicke cosmology with constant vacuum energy density (BD-$\Lambda$CDM) may be able to…

宇宙学与河外天体物理 · 物理学 2021-10-04 Adrià Gómez-Valent , Prajwal Hassan Puttasiddappa

In this exposition, we seek solutions of the Einstein-Maxwell field equations in the presence of a massive scalar field cast in the Brans-Dicke (BD) formalism which describes charged anisotropic strange stars. The interior spacetime is…

广义相对论与量子宇宙学 · 物理学 2020-12-08 S. K. Maurya , Ksh. Newton Singh , M. Govender , Abdelghani Errehymy

We have studied a superbounce scenario in a set up of Brans-Dicke (BD) theory. The BD parameter is considered to be time dependent and is assumed to evolve with the Brans-Dicke scalar field. In the superbounce scenario, the model bounces at…

广义相对论与量子宇宙学 · 物理学 2023-03-28 S. K. Tripathy , S. K. Pradhan , B. Barik , Z. Naik , B. Mishra

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

The dependence of Brans-Dicke (BD) parameter upon the scalar field, for different cosmological era of the expanding universe, has been explored. The time dependence of the scalar field has been determined and thereby the explicit time…

广义相对论与量子宇宙学 · 物理学 2017-06-23 Sudipto Roy , Soumyadip Chowdhury

We study anisotropic inflation in the Brans-Dicke gravity in the presence of an abelian gauge field where the gauge field is non-minimally coupled to the inflaton. We show that the degree of anisotropy, under slow-roll approximations, is…

广义相对论与量子宇宙学 · 物理学 2017-11-03 M. Tirandari , Kh. Saaidi

We investigate the cosmological observational test of the extended quintessence model, i.e. a scalar-tensor gravity model with a scalar field potential serving as dark energy, by using the Planck 2018 cosmic microwave background (CMB) data,…

宇宙学与河外天体物理 · 物理学 2021-05-26 Gong Cheng , Fengquan Wu , Xuelei Chen

We present constraints on modified gravity from a cosmic shear analysis of the final data release of the Kilo-Degree Survey (KiDS-Legacy) in combination with DESI measurements of baryon acoustic oscillations, eBOSS observations of redshift…

Brans-Dicke (BD) cosmology is reconsidered from an approach in which the model can be formulated in $\Lambda$CDM form, but at the expense of replacing the rigid cosmological constant $\Lambda$ with a dynamical quasivacuum component which…

广义相对论与量子宇宙学 · 物理学 2018-11-29 Javier de Cruz Perez , Joan Sola

We introduce a cosmological model based on the normal branch of DGP braneworld gravity with a smooth dark energy component on the brane. The expansion history in this model is identical to LambdaCDM, thus evading all geometric constraints…

宇宙学与河外天体物理 · 物理学 2018-08-02 Fabian Schmidt

In this work, we have studied the Brans-Dicke (BD) cosmology in anisotropic models. We present three dimensional dynamical system describing the evolution of anisotropic models containing perfect fluid and BD scalar field with…

综合物理 · 物理学 2011-12-30 Jhumpa Bhadra , Shuvendu Chakraborty , Ujjal Debnath

In this paper, we derive a 90\% credible lower bound on the modified parameter of scalar-tensor theories as $\varphi_{-2}>-7.94\times10^{-4}$ by using dominant-mode correction. Specific to BD theory, we have the constraint $\omega_{\rm…

广义相对论与量子宇宙学 · 物理学 2024-04-30 Jing Tan , Baoxiang Wang

A type of exponential correction to General Relativity gives viable modified gravity model of dark energy. The model behaves as $R-2\Lambda$ at large curvature where an effective cosmological constant appears, but it becomes zero in flat…

广义相对论与量子宇宙学 · 物理学 2022-01-13 L. N. Granda

We present a full-fledged analysis of Brans-Dicke cosmology with a cosmological constant and cold dark matter (BD-$\Lambda$CDM for short). We extend the scenarios where the current cosmological value of the BD-field is restricted by the…

宇宙学与河外天体物理 · 物理学 2020-11-30 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez , Cristian Moreno-Pulido
‹ 上一页 1 2 3 10 下一页 ›