Cosmology in the Hoyle Narlikar gravity

TL;DR

This work investigates late-time cosmic acceleration within Hoyle–Narlikar gravity by incorporating a creation field with non-minimal matter interaction in a flat FLRW setting. It derives the modified field equations, adopts a specific $H(z)$ parametrization, and links cosmic time to redshift to study the model’s dynamical evolution.Parameter constraints are obtained via MCMC using $H(z)$, Pantheon$^+$, and BAO data, revealing consistent acceleration and a viable alternative to ΛCDM with a C-field driving the late-time dynamics. Cosmographic diagnostics show the model approaches ΛCDM at late times, with $q$ transitioning from positive to negative, $j(z)$ near 1, and a thawing–freezing w–$w'$ behavior that reinforces stability and observational viability.

Abstract

In this paper, we study the late time cosmic acceleration of the Quintessence model within the framework of Hoyle Narlikar Gravity, consisting of a creation field. Using the Hubble tension as a function of the density parameter for matter, the density parameter for radiation, and the density parameter for dark energy in the covariant formulation, we find the gravitational field equations in the spatially flat, homogeneous, and isotropic spacetime to examine the dynamical mechanism that leads to cosmic acceleration in the late-time universe. We analyze the observational constraints on the late-time density parameters using various recent observational datasets, including the Hubble datasets, Pantheon+, and joint compilation, Pantheon++BAO. Consequently, it is explicitly demonstrated that late-time cosmic acceleration can be consistent with recent observational data in Hoyle Narlikar Gravity with non-minimal matter interaction. In contrast with other modified theories of gravity, it is observed that the creation field theory with non-minimal matter interaction renders more compact constraints on the Hubble tension together with density parameters, and extensively explains the accelerating expansion of the universe, which makes it a more plausible option compared to the ΛCDM model. Furthermore, the w dw phase analysis confirms alternating thawing and freezing behaviour of the model, with all trajectories ultimately converging toward the ΛCDM point, thereby confirming the model stability and the observational consistency.

Figures (11)

• Figure 1: The evolution of the creation field $\mathcal{C}$ in terms of time $t$ with $k = 0.18$ and $\alpha = 1.05$.
• Figure 2: Posterior distributions for the model parameter pairs with the iso-surfaces correspond to 1$\sigma$ and 2$\sigma$ CLs for all data compilations.
• Figure 3: The Error Bar plots exhibit the consistency of our model with the $\Lambda$CDM model across all data compilations.
• Figure 4: Covariance and correlation matrices among the model parameters for all data compilations.
• Figure 5: Cosmic evolution of the deceleration parameter ($q$) and the jerk parameter ($j$) for all data compilations.