A New f(R) Model in the Light of Local Gravity Test and Late-time Cosmology

TL;DR

This paper introduces a novel f(R) gravity model with an Arctan function, demonstrating its consistency with local gravity tests and analyzing its cosmological implications, including comparison with ΛCDM and observational data fitting.

Contribution

The paper presents a new f(R) gravity model with an Arctan function, satisfying fifth force constraints and analyzing its cosmological evolution and observational viability.

Findings

Model satisfies fifth force constraints.

Cosmological evolution differs from ΛCDM as shown by Om diagnostic.

Best-fit parameters obtained from BAO data.

Abstract

We propose a new model of f(R) gravity containing Arctan function in the lagrangian. We show here that this model satisfies fifth force constraint unlike a similar model in Kruglov 2013. In addition to this, we carry out the fixed point analysis as well as comment on the existence of curvature singularity in this model. The cosmological evolution for this f(R) gravity model is also analyzed in the Freidmann Robertson Walker(FRW) background. To understand observational significance of the model, cosmological parameters are obtained numerically and compared with those of Lambda cold dark matter ({\Lambda}CDM) model. We also scrutinize the model with supernova data. We apply Om diagnostic given by Sahni et al. 2008 to the model. Using this diagnostic, we detect the distinction between cosmic evolution caused by the f(R) model and {\Lambda}CDM. We find best-fit parameter values of the model using Baryon Acoustic Oscillations data.