Constraining phantom braneworld model from cosmic structure sizes [CL]

http://arxiv.org/abs/1706.06268


We consider the phantom braneworld cosmology in the context of the maximum turn around radius, $R_{\rm TA,max}$, of spherical cosmic structures. The maximum turn around radius is the point where the attraction due to the central inhomogeneity gets balanced with the repulsion of the ambient dark energy, beyond which a structure cannot hold any mass, thereby giving the maximum upper bound on the size of a stable structure. In this work we first derive an analytical expression of $R_{\rm TA,max}$ for this model. Using this we constrain its parameter space, including a bulk cosmological constant and the Weyl fluid, from the mass versus actual observed size data for some nearby large scale structures. We show in particular that a) in the absence of any bulk cosmological constant the predicted maximum size is always greater than what is actually observed b) same conclusion holds upon inclusion of a negative bulk cosmological constant and c) if the bulk cosmological constant is positive, the predicted maximum size can go below than what is actually observed, leading to interesting constraints on the parameter space of the theory

Read this paper on arXiv…

S. Bhattacharya and S. Kousvos
Wed, 21 Jun 17
14/64

Comments: v1; 16pp, 3 figures