Universe in f(R,G) gravity with special form of q.

Tiwari, R. K.; Shukla, Bhupendra Kumar; Beesham, A.; Agrawal, Sudha

This paper explores the dynamic behavior of the universe within the framework of the f (R , G) theory of gravity. Here, R and G represent the Ricci scalar and Gauss–Bonnet invariant, respectively. By solving the modified field equations with the chosen f (R , G) function, specifically f (R , G) = R m R 2 n G 2 , we determine the best fit values of model parameters that are consistent with recent observational datasets. These datasets include 57 data points from the Cosmic Chronometers, Pantheon, and BAO datasets. Furthermore, we analyze the physical properties of cosmographic parameters, such as energy density and pressure, corresponding to the constrained values of the model parameters. The evolution of the deceleration parameter in our study indicates a transition from a decelerated phase to an accelerated phase in the universe. Remarkably, our f (R , G) cosmological model effectively describes the late-time cosmic acceleration without requiring the introduction of a dark energy component in the field equations.

GRAVITY; UNIVERSE; DARK energy; ENERGY density; ACCELERATION (Mechanics); CHRONOMETERS

International Journal of Geometric Methods in Modern Physics, 2024, Vol 21, Issue 3, p1

0219-8878

Academic Journal

10.1142/S0219887824500695