Cosmic dynamics unveiled in Chern–Simons modified gravity with holographic dark energy model

This study provides a comprehensive analysis of the Friedmann–Robertson–Walker model within Chern–Simons modified gravity, incorporating the holographic dark energy model. The scale factor, deceleration parameter, Hubble parameter, and cosmological constants ( \(\Lambda \) $\mathrm{\Lambda }$ and G) are examined. The findings help to distinguish between models of acceleration and deceleration, supporting recent data that indicate an accelerating universe. The decreasing trend observed in the cosmological constant \(\Lambda (t)\) $\mathrm{\Lambda }(t)$ aligns with type Ia supernovae observations. Additionally, the observed correlation between the gravitational constant G(t) and cosmic time supports specific critical density assumptions. State finder parameters (r, s) offer insights into various cosmological scenarios. Overall, this study advances our understanding of the universe’s evolving nature under the FRW model with Chern–Simons modified gravity.