Allow me to preface the following with an apology if the question I ask sseem a bit off. While reading Coming Of Age In The Milky Way by Timothy Ferris I came across a line in which he states: "Earths gravitational force extends from its center point" My understanding of gravity is that it is nothing more than curved space-time. The mass of objects warp the space-time and that warping is what produces the attractive force. Why would the earth's gravitational force extend from its center point. How can the center of the earth warp space-time unless space-time exists within the earth at its center? Wouldn't the outer edges of earth's surface be the source of the space-time warping since that is the area which comes in "contact" with space-time?