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General Relativity is one the most profound achievements in science, combining mathe-matical elegance with over a century of empirical validation.
Nevertheless, both observational and theoretical developments have revealed limitations in General Relativity. Particularly, the discovery of the accelerated expansion of the uni-verse highlights its inability to naturally account for dark energy without invoking a fine tuned cosmological constant. In response, a wide range of modified gravity theories have been proposed. Among these, Teleparallel Gravity and Symmetric Teleparallel Gravity, formulated within non-Riemannian geometry, have gained increasing attention in recent years.
In this work, we investigated extensions of these alternative theories, focusing on their ability to reproduce the late-time acceleration of the universe by mimicking the effects of a cosmological constant. We further subjected these models to local gravitational constraints by analyzing their predictions in static, spherically symmetric spacetimes. Our results demonstrate that while several models can successfully replicate cosmological acceleration, many are inconsistent with Solar System observations, notably through deviations in the Eddington parameter. This highlights the importance of combining cosmological and local tests when assessing the physical viability of modified gravity theories.