Role of dark energy on maximum mass, stability, and structure: Theoretical insights into relativistic compact stars

In this work, we explore a novel class of exact solution that shed light on the properties of compact stars formed from dark energy (DE), framed within the framework of general relativity. Our study investigates the structural and stability characteristics of DE compact stars, focusing on the effects of the DE parameter [Formula: see text] and the dark anisotropy parameter [Formula: see text]. Our analysis reveals that the metric potentials [Formula: see text] and [Formula: see text] are free from singularities and remain positive throughout the stellar configuration. Importantly, [Formula: see text] is sensitive to variations in [Formula: see text] and [Formula: see text], indicating significant modifications to spacetime geometry due to DE. We find that increasing [Formula: see text] and [Formula: see text] leads to a reduction in density while enhancing pressure, thereby impacting the star’s internal equilibrium. Although the energy conditions are generally satisfied, DE tends to weaken some of these conditions, particularly near the surface. Stability analysis using the modified Tolman–Oppenheimer–Volkoff (TOV) equation confirms that hydrostatic pressure effectively balances gravitational and DE forces. Additionally, our investigation into the mass–radius relation highlights the influence of DE on the upper mass limit of neutron stars (NSs). The mass–radius relationship demonstrates that mass increases with radius up to a peak before sharply declining. The maximum mass values obtained range from [Formula: see text] to [Formula: see text], with radii between [Formula: see text] km and [Formula: see text] km, consistent with observed stellar data. As the DE parameter [Formula: see text] increases, both the maximum mass and the predicted radius for a given mass decrease, indicating that DE weakens gravitational binding, resulting in less massive and less dense stellar configurations. This challenges traditional mass limits predicted by general relativity and suggests that DE plays a crucial role in shaping the stability and structure of compact stars.