what is the path of earth in 4-d space?? as i read in the brief history of time "let a plane be moving straight in 3-d world but we see it in a curved path on a 2-d earth surface (mountain). can any1 tell how can we see the space curve as 2-d has not elevation?? moreover i used to think that bodies with mass curve the 4-d space like a paper weight (sun) curves a trampoline and object like Table tennis ball (earth) which try to move in straight path in 4-d space will be disturbed by their path and revolve around the center (as the earth to sun) and will get closer and closer and will reach the center in some time (millions of year when talking about sun and earth) and in secs in our model (trampoline) . Am i having a misconception?