Newton’s theory of gravity held its ground for more than two hundred years until Einstein published his paper on General theory of relativity in 1915. General theory of relativity gives a geometric description of gravitation. As seen today, gravity is not considered to be an alien force travelling through space and time, but as a curvature in space-time. Motion viewed by Galileo and Newton was with respect a fixed Euclidean reference frame. In this ideal frame of reference Newton and Galileo built up and described this strange force of gravity without giving a geometry description about it. But Einstein argued that there is no such force as gravity, it’s just a curvature in space-time or an observed acceleration due to this curvature in space-time. Newton Consider time as an absolute constant something which is independent of any influence, claiming this on basis of Euclidean reference frame which accounted for all of space and all of time. But Einstein said the exact …show more content…
It was natural for him to generalize the idea of WEP by arguing that there should be no way for the physicist inside the box to differentiate between gravitational field and uniform acceleration. This concept later came to be known as Einstein Equivalence principle. Hence Einstein Equivalence principle suggests that we should attribute effects of gravity to curvature of space-time. Einstein Equivalence principle also puts forth that there is no such thing a gravitationally neutral object with respect to which we can measure acceleration due to gravity. Hence it is more convenient for us to define ‘nonaccelerating bodies’ as ‘free-falling’. Therefore we may conclude that gravity is not a force because a force is something which results into acceleration. But we have defined zero acceleration to be free motion of a body in any kind of gravitational