Time in special relativity and its philosophical significance

Abstract

Two opposing views about the significance of the concept of time occurring in the special theory of relativity are discussed. The first view is that relativistic time is inherently 'conventional' and therefore not of importance for questions about the nature of reality. The other is that the structure of relativistic time shows that we live in a four-dimensional 'block universe', in which past and future are mere illusions. Against the first position the author argues that relativistic time is no more conventional than time in classical physics; it is equally 'real'. But this by itself does not mean that the second position is right. It does not follow from the relativistic structure of time that past and future, and a shifting 'now', are unreal. This is because there is a fundamental difference between the physical concept of time and the notion of time occurring in the doctrine of the shifting 'now'.