The Equivalence of Gravitational and Inertial Mass
A unique feature of the gravitational force is that all massive objects accelerate in the same manner in a gravitational field. This is often expressed as "The gravitational mass is equal to the inertial mass." This allows us to think of gravity as a curvature of spacetime. Objects move in spacetime along geodesics, the paths which yield the shortest distance between two points in spacetime.
Read more about this topic: Newtonian Motivations For General Relativity
Famous quotes containing the word mass:
“In the mass of mankind, I fear, there is too great a majority of fools and knaves; who, singly from their number, must to a certain degree be respected, though they are by no means respectable.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)