The article explores whether the current cosmic acceleration can be explained by modifications to general relativity rather than dark energy. The authors propose that small corrections to the Einstein-Hilbert action, such as $ R^n $ with $ n < 0 $, can lead to self-accelerating vacuum solutions, offering a purely gravitational alternative to dark energy. This approach eliminates the need for dark energy but does not resolve the cosmological constant problem. The model also allows for early-time inflation through modifications with $ n > 0 $, providing a unified explanation for both early and late-time cosmic acceleration. The model involves a modified gravitational action with a term $ -\mu^4 / R $, leading to a scalar field potential $ V(\phi) $ that influences the cosmological evolution. The field equations in the Einstein frame are derived, showing that the universe can evolve through different phases: eternal de Sitter, power-law acceleration, or a future curvature singularity, depending on initial conditions. The model is consistent with current cosmological observations and passes solar system tests, as the modifications do not affect the Schwarzschild solution when $ \mu $ is sufficiently small. The paper also discusses the possibility of other forms of modifications to the Einstein-Hilbert action, such as $ -\mu^{2(n+1)}/R^n $, which can yield similar effects. These modifications can accommodate current observational constraints on the equation of state parameter $ w_{\text{DE}} $. The authors conclude that cosmic acceleration can arise from purely gravitational effects, offering a compelling alternative to dark energy. However, the model requires further testing and analysis of perturbations and the transition from matter domination to self-acceleration. The study highlights the potential for new gravitational physics to explain cosmic acceleration without invoking dark energy.The article explores whether the current cosmic acceleration can be explained by modifications to general relativity rather than dark energy. The authors propose that small corrections to the Einstein-Hilbert action, such as $ R^n $ with $ n < 0 $, can lead to self-accelerating vacuum solutions, offering a purely gravitational alternative to dark energy. This approach eliminates the need for dark energy but does not resolve the cosmological constant problem. The model also allows for early-time inflation through modifications with $ n > 0 $, providing a unified explanation for both early and late-time cosmic acceleration. The model involves a modified gravitational action with a term $ -\mu^4 / R $, leading to a scalar field potential $ V(\phi) $ that influences the cosmological evolution. The field equations in the Einstein frame are derived, showing that the universe can evolve through different phases: eternal de Sitter, power-law acceleration, or a future curvature singularity, depending on initial conditions. The model is consistent with current cosmological observations and passes solar system tests, as the modifications do not affect the Schwarzschild solution when $ \mu $ is sufficiently small. The paper also discusses the possibility of other forms of modifications to the Einstein-Hilbert action, such as $ -\mu^{2(n+1)}/R^n $, which can yield similar effects. These modifications can accommodate current observational constraints on the equation of state parameter $ w_{\text{DE}} $. The authors conclude that cosmic acceleration can arise from purely gravitational effects, offering a compelling alternative to dark energy. However, the model requires further testing and analysis of perturbations and the transition from matter domination to self-acceleration. The study highlights the potential for new gravitational physics to explain cosmic acceleration without invoking dark energy.