Born-Infeld gravity with a Brans-Dicke scalar

Jana, Soumya and Kar, S (2017) Born-Infeld gravity with a Brans-Dicke scalar. arXiv. (Submitted)

[img]
Preview
Text (arXiv copy)
1706.03209.pdf - Accepted Version

Download (425kB) | Preview

Abstract

Recently proposed Born-Infeld (BI) theories of gravity assume a constant BI parameter (κ). However, no clear consensus exists on the sign and value of κ. Recalling the Brans-Dicke (BD) approach, where a scalar field was used to generate the gravitational constant G, we suggest an extension of Born-Infeld gravity with a similar Brans-Dicke flavour. Thus, a new action, with κ elevated to a spacetime dependent real scalar field, is proposed. We illustrate this new theory in a cosmological setting with pressureless dust and radiation as matter. Assuming a functional form of κ(t), we numerically obtain the scale factor evolution and other details of the background cosmology. It is known that BI gravity differs from GR in the strong field regime but reduces to GR for intermediate and weak fields. Our studies in cosmology demonstrate how, with this new, scalar-tensor BI gravity, deviations from GR as well as usual BI gravity, may arise in the weak field regime too. For example, we note a late-time acceleration without any dark energy contribution. Apart from such qualitative differences, we note that fixing the sign and value of κ is no longer a necessity in this theory, though the origin of the BD scalar does remain an open question.

[error in script]
IITH Creators:
IITH CreatorsORCiD
Jana, SoumyaUNSPECIFIED
Item Type: Article
Subjects: Electrical Engineering > Electrical and Electronic
Divisions: Department of Electrical Engineering
Depositing User: Team Library
Date Deposited: 19 Jun 2017 06:29
Last Modified: 12 Sep 2017 08:39
URI: http://raiith.iith.ac.in/id/eprint/3254
Publisher URL:
Related URLs:

Actions (login required)

View Item View Item
Statistics for RAIITH ePrint 3254 Statistics for this ePrint Item