The theory of relativity was formulated by German physicist Albert Einstein (1879 -1955), who in 1905 published the first studies on this topic. Through relativity states that the universe does not exist in absolute measures, and explains the new concepts of movement, time and space. We define that all motion is relative. For example, the train is moving relative to the station seemed static, but it also moves due to the shifting of the Earth. The same happens with time, which is not absolute but varies with the speed of the body on which it is measured. With respect to space, this theory also employs an absolute unit of measure: the space covered by a body is measured in accordance with the schemes to be confronted. For example, if an object falls from a ninth floor, the vision of space travel depends on whether the observer is on the ground floor, a plane or on another planet.
The theory of general relativity provides the equivalence between a system under the force of gravity and an accelerated system without gravitational field where the elements and creatures floating in space.