Proof
Einstein also wrote that observations are dependent on the frame of reference - and since we don't have another frame of reference other then our own - is it not conceivable that the current "observation" of facts are incorrect?
I throw a baseball to you at 10 MPH, since we are both...
Most of us know about the three dimensions - x,y,z (space), and by adding time we get a 4-dimensional space-time continum.
Some of our "genius" friends at NYU (and other places) believe that gravity is the result of the planets (and other objects) traveling around the dimple it creates in...