I read from a physics website that says that an accelerating object experiences different acceleration throughout its structure according to special relativity. I never thought of that! "In special relativity, one finds that when a spacecraft maintains its structural integrity, so that the distance from tail to nose is constant for passengers in the spacecraft, it experiences different rates of acceleration throughout its structure. The nose of the spacecraft accelerates at a lower rate than the tail of the spacecraft; the amount of acceleration depends solely on position along the direction of acceleration. The acceleration increases as one moves back. Because time dilation is determined by the rate of acceleration, a passenger in the spacecraft finds that a clock placed in the nose of the spacecraft moves faster than a clock placed in the tail." http://www.astrophysicsspectator.com/topics/specialrelativity/Accelerated.html If that is the case, is it true that inside an rocket accelerating in one direction, the ceiling and and the floor have different rate of acceleration (less acceleration for the ceiling and more acceleration for the floor)? What is the explanation behind this?