Q&A: The Objectivity of Time in Special Relativity
The Objectivity of Time in Special Relativity
Question
Hi,
Relativity denies the assumption that in inertial systems there is an objective and universal time from the standpoint of measurement. That is, it claims that every actual measurement of time receives its meaning relative to the observer and the speed of that observer’s motion.
Isn’t that claim itself a universal and objective claim about time? At the very least, is it not a universal and objective claim about a common denominator imposed on all observers?
Answer
The theory of relativity is often presented as a parable for relativistic thought—that is, for the absence of one absolute truth. But that is a mistake made by philosophers who understand nothing about physics. The whole theory of relativity was built so that the laws of nature would be uniform in all systems, and the “price” is changes in space and time. So you do not need to arrive at that sweeping claim in order to show an objective truth. All the laws of nature are like that.
So too with non-Euclidean geometries, which are also used to illustrate the relativism of our thought. And that is, of course, nonsense again. Every geometry describes a different space, and for every given space there is one geometry (metric) and no other. Therefore, the multiple geometries actually illustrate monism very well (that is, that there is only one truth).
Discussion on Answer
That is part of the laws of nature and therefore universal. But time itself is not universal, since measurements of it yield different results.
Thanks. I of course think more or less like you, but my question was more focused: is the time described by special relativity universal and objective? I’m asking not about “truth” or “reality” in general, but only about measured time.