It’s about time for a timely discussion about time.
In about 397 ACE, St. Augustine confessed, “I know well enough what time is, provided nobody asks me, but if I am asked what it is and try to explain, I am baffled.” (St. Augustime, Confessions Book 11, ca 397 AD,). He then went on to explain, “ if nothing has passed, there could be nothing we could call past time; if nothing were to happen, there would be nothing we could call future time, and if nothing were at all, there would be nothing we could call present time.”
He has here concisely expressed one of the fundamental problems in our conception of time. The mathematical cosmologists have, however, given us many more problems to think about, most of them since the publication of Einstein’s Theory of General Relativity in 1915. Before Einstein, there were many philosophical and scientific discussions of the nature of time, such as:
• “This present moment is common to all things that are now in being, and equally comprehends that part of their existence as much as if they were all but one single being, and we may truly say, they all exist in the same moment of time.”
(Locke, Essays, bk. 2, ch. 15, pa. 11; 1690)
• “Absolute, true, and mathematical time of itself and from its own nature, flows equably without relation to anything external, and by another name is called duration.” (Newton; Principia, 1687)
As we shall see later, Newton was almost there.
Albert Einstein was one of the first to give to time a substantive place, as a substantive element in the nature of reality. For Einstein, time was one of the four principal “dimensions” of reality, along with length, breadth, and depth. He then defined “spacetime”, his new, 4-dimensionsl entity, as having many unique characteristics. It could be flat or curved in many different ways. It could be manipulated, described mathematically. Belief in it could open up many new ways of imagining the nature of reality. It could lead to a dizzying number of theories of the universe, and it has.
But what if this concept of time is wrong? What if there were another way to understand the nature of what we call time? How would this affect the mathematical cosmos that we seem to have accepted as reality, even though it may be only describable in mathematical formulae?
To puzzle this image out, let’s look at a simple phenomenon we call an object, perhaps a small cube, and apply these 4 dimensions to it. First, as it exists before our eyes, we can see that it has length, from right to left; it has depth, from front to back; it has height, from top to bottom. We can describe it by saying that it is x inches wide, it is y inches high, and z inches deep. But can we say that it is t seconds time? No, we wouldn’t normally do that. Length, width and depth are obvious qualities that adhere to this object, that are part of its essence, so to speak. But “time” is not. The real fourth dimension that this object has is its persistence in the space that it occupies. Newton hinted at this in saying that time “by another name is called duration”.
We measure that persistence in units of time, in everything from picoseconds to millennia and beyond. (It should be noted also that persistence also has to be considered a so-called “killer” dimension, because without it, the object could have none the other three qualities.
So, can we place this new (old) vision of time in Einstein’s theory of General Relativity, and subsequently, in all of the imagined worlds and universes that theory has spawned? It seems like a difficult task. Persistence would seem resistant to being “curved”, and there goes one of the current definitions of gravity. Persistence can, of course be measured, as in how long has this object existed here on the table before us? how long, if it is moving, has it persisted on this particular course or track? and so on. But without the mathematical formulae based on General Relativity (and don’t even try to estimate how many of those are out there!) is there possibly another way to describe the nature of the universe, its origins, its growth, its complexity, its diversification, its expansion? A new look seems to called for.
Two other thoughts on the nature of time have amused me:
• A teacher, after explaining to his class the concept of time zones around the world, asks, “Who can tell me what time it is in Moscow?” After a moment, a little girl replies, “Isn’t it now?” (do you suppose she has read Locke?)
and one which seems to have more than a kernel of truth in it, as all good jokes have:
• “Time is just one damn thing after another.”