Cosmological Solutions of Tensor–Vector Theories of Gravity by Varying the Space-Time–Matter Coupling Constant

Journal of astrophysics and astronomy

A. Shojai²  A. Izadi1¹  M. Nouradini² 

[1] Department of Physics, K. N. Toosi University of Technology, Tehran, Iran.$$;Department of Physics, University of Tehran, North Karegar Ave., Tehran, Iran.$$

关键词: Speed of light;    tensor;    vector theories;    dynamical system method;    horizon problem.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

We consider tensor–vector theories by varying the space-time–matter coupling constant (varying Einstein velocity) in a spatially flat FRW universe.We examine the dynamics of this model by dynamical system method assuming a 𝛬CDM background and we find some exact solutions by considering the character of critical points of the theory and their stability conditions. Then we reconstruct the potential 𝑉(𝐴2) and the coupling 𝑍(𝐴2) by demanding a background 𝛬CDM cosmology. Also we set restrictions on the varying Einstein velocity to solve the horizon problem. This gives a selection rule for choosing the appropriate stable solution. We will see that it is possible to produce the background expansion history 𝐻(𝑧) indicated by observations. Finally we will discuss the behavior of the speed of light (𝑐E) for those solutions.

【 授权许可】

Unknown