Final answer:
Einstein's modifications to Newton's universal law of gravitation, known as his general theory of relativity, explain the deviations from classical predictions. These deviations are most noticeable in extremely large gravitational fields, such as near black holes, but can also be observed in the small but long-known deviations of the orbit of the planet Mercury.
Step-by-step explanation:
Einstein's modifications to Newton's universal law of gravitation, known as his general theory of relativity, explain the deviations from classical predictions. These deviations are most noticeable in extremely large gravitational fields, such as near black holes, but can also be observed in the small but long-known deviations of the orbit of the planet Mercury. Einstein's theory of general relativity states that the presence of matter curves or warps the fabric of spacetime, which affects the motion of objects within it.