Einstein's general theory of relativity successfully explained the anomalous precession of Mercury's perihelion, which had puzzled scientists for many years. The precession of Mercury's orbit refers to the gradual rotation of the ellipse that describes its path around the Sun. General relativity provided a theoretical framework to account for this precession by considering the curvature of spacetime caused by the Sun's mass.
To date, numerous observations and experiments have supported the predictions of general relativity, including the explanation for the precession of Mercury's perihelion. However, science is an ongoing process, and it is always possible for new observations or theories to emerge that might challenge or refine our current understanding.
Regarding your suggestion that the precession could be caused by a gravitational kick the Sun gives to Mercury per revolution, it is important to note that scientific theories are not developed based on arbitrary assumptions but rather through a process of rigorous observation, testing, and mathematical modeling. Einstein's general relativity has successfully explained not only the precession of Mercury but also many other phenomena, such as gravitational lensing and the bending of starlight.
While it is possible that future discoveries could lead to modifications or refinements of our current understanding of gravity, any new theory or explanation would need to be consistent with existing observations and provide a more accurate description of the observed phenomena. The robustness and consistency of general relativity, combined with its success in explaining a wide range of gravitational phenomena, make it a highly regarded and widely accepted theory in modern physics.
Therefore, while scientific knowledge can evolve and be refined over time, at present, Einstein's general relativity remains a well-established and highly successful theory for explaining the precession of Mercury's perihelion and many other gravitational phenomena.