Anisotropic Cosmic Evolution and Statefinder Diagnostics of a Bianchi Type VI0 Universe with Hybrid Scale Factor in f(R, Lm) Gravity
Abstract
We investigate the dynamics of an anisotropic Bianchi type VI₀ cosmological model within the framework of f(R, Lm) gravity by adopting a curvature–matter coupled form f(R, Lm) = R/2 + Lαm. A hybrid expansion law a(t) = expβt tγ is employed to describe the cosmic evolution, allowing a smooth transition from an early decelerated phase to a late-time accelerated expansion. The parameter α = 0.4 is chosen to ensure stable and physically viable behavior of the model. The analysis shows that the scale factor and spatial volume increase monotonically with cosmic time, indicating a continuously expanding universe. The deceleration parameter exhibits a transition from positive to negative values and approaches the de Sitter limit at late times. The equation of state parameter evolves from a matter-dominated regime toward the quintessence region and asymptotically approaches ω = −1. The energy density remains positive and decreases with time, while the pressure stays negative throughout the evolution, supporting accelerated expansion. Furthermore, the statefinder diagnostics in the {r, s} and {r, q} planes demonstrate that the model deviates from standard cosmology at intermediate epochs and converges to the ΛCDM fixed points at late times. These results indicate that the proposed model provides a consistent and viable description of dark energy-driven cosmic evolution.
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