Eddington-inspired Born-Infeld Gravity with Varying Cosmological Constant

TL;DR

This paper modifies the EiBI gravity model to include a matter-dependent varying cosmological constant and Newton's constant, exploring its implications for early universe behavior and singularity avoidance.

Contribution

It introduces a new version of EiBI gravity with a dynamic cosmological constant linked to matter distribution, extending previous models.

Findings

Varying cosmological and Newton's constants are related and matter-dependent.

Different forms of pending functions lead to diverse early universe behaviors.

Singularity avoidance is possible in this modified model.

Abstract

In this paper we modify the EiBI model to realize a varying cosmological constant which is determined by matter distribution. We find that the Newton's constant is also variable and its change is related to the change of cosmological constant. And then we study its cosmological behavior. We find that the early universe will have different behaviors if we take different forms of pending functions. And we can avoid singularity in early universe just like the original EiBI model.