How do gravitational forces affect the way planets move?
Einstein’s theory of General Relativity (1915) is a cause and effect theory. The theory describes the fabric of space-time as a medium that may be distorted by the presence of mass and energy. From his earlier relativity theory, Einstein had related mass and energy in the famous equation: – E = mc² From this concept, he described the curvature or distortion of space-time as due to the total sum of mass-energy present within the region of distorted space. It is the curvature of space-time we call gravity. Thus, our planet follows the ‘straightest’ path or path of least action whilst it orbits the mutually curved space around the Sun. An object falling to earth, under the pull of gravity, is following the curvature of space in the region around the surface of the Earth. Einstein described the relationship between space-time curvature and the mass-energy causing it, in the tensor field equation: – G = 8πT Where ‘G’ is the Einstein tensor representing the ‘gravity’ or curvature of space-ti
