Einstein's theory of relativity, which encompasses both special relativity and general relativity, is widely accepted and considered one of the cornerstones of modern physics. It has been extensively tested and validated through various experiments and observations over the past century. However, it is important to understand that scientific theories are not accepted or rejected solely based on the work of a single individual, no matter how influential they may be.
Newton's theory of gravity, known as Newtonian gravity, was developed in the late 17th century and was incredibly successful in explaining the motion of objects on Earth and in the solar system. It provided accurate predictions for a wide range of everyday phenomena and was widely accepted for centuries.
Einstein's theory of relativity introduced a more comprehensive and accurate description of gravity, especially in extreme conditions involving high speeds, strong gravitational fields, and cosmological scales. However, because the differences between Newtonian gravity and general relativity become significant only in extreme situations, such as near massive objects or in the presence of very high speeds, Newton's theory still provides a sufficiently accurate approximation for many everyday situations.
Additionally, the principles and equations of Newtonian gravity are much simpler and easier to work with compared to the complex mathematics involved in general relativity. This makes Newton's theory more accessible and practical for many applications where the additional precision provided by general relativity is unnecessary.
In essence, while general relativity has largely superseded Newtonian gravity in situations where relativistic effects are significant, Newton's theory continues to be used and taught because it is simpler, more intuitive, and accurate enough for many practical purposes. Nonetheless, it is crucial to note that general relativity is the more complete and accurate description of gravity, as it encompasses and extends Newton's ideas in a broader framework.