Compact stars in Ricci inverse gravity with matter trace effects

This study examines isotropic compact structures in the framework of Ricci inverse gravity with a trace term [Formula: see text], which introduces anti-curvature scalar and matter-geometry coupling beyond general relativity. This modified theory extends general relativity by introducing an inverse curvature correction alongside a non-minimal coupling between matter and geometry, enabling a deeper understanding of gravitational effects in high-density regimes. Using a static spherically symmetric metric and applying the Karmarkar condition, we derive class-I solutions by fixing one metric potential [Formula: see text] and determining the other accordingly. The model is applied to known compact stars [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] and evaluate the unknown constants present in the metric tensors. A detailed analysis of energy density and pressure cocomponent, energy conditions, stability, redshift, and mass–radius relation confirms that the model supports realistic stellar configurations. The results suggest that Ricci inverse gravity with trace term [Formula: see text] offers a promising extension for modeling dense astrophysical objects.