General Relativity

General relativity is a theoretical framework in physics formulated by Albert Einstein in 1915, which describes the gravitational force as a curvature of spacetime caused by the presence of mass and energy. It replaces Newton's law of universal gravitation, providing a more comprehensive explanation of gravitational interactions, especially in extreme conditions such as those near massive objects like stars and black holes.In general relativity, objects in free fall are seen as moving along the straightest possible paths in a curved spacetime, which is a four-dimensional continuum that combines the three spatial dimensions with time. The key equation of general relativity, the Einstein field equations, describes how matter and energy in the universe influence the curvature of spacetime. General relativity has been confirmed through numerous experimental tests and observations, and it has profound implications for our understanding of cosmology, black holes, and the expansion of the universe.