Motion in Einstein's theory of relativity and comparisons with classical views

Abstract

Abstract

In everyday terms, as in Newtonian physics, ‘motion’ refers to a change of the position of an object in space with respect to a time change. That is to say, a continuous time change parameterizes a continuous spatial change along the trajectory of the object in motion. But in the later development of physics, particularly in the continuous field view that comes with Einstein's theory of relativity, ‘motion’ is a general type of change, not necessarily with respect to a time change. These differences in the meaning of the motion of matter in the classical atomistic view and the continuous field view will be addressed in this paper. Also discussed will be the question as to whether or not the ‘motion’ of matter is an absolute, objective quality of matter, or rather a subjective quality, dependent on the reference frame of the observer.