Time exists but the movement of time or its flow is subjective. It is something that depends only on our perception. That's what Max Tegmark, physicist at Massachusetts Institute of Technology explains in his book Our Mathematical Universe: My Quest for the Ultimate Nature of Reality.
It certainly feels to us like time is flowing. Yet that’s not the only way of looking at this reality. I could say that 10 to the power of 29 particles constitute me, and they are moving around in some very complicated patterns. Einstein pointed out that the most elegant way of describing this mathematically is to say, Let’s look at where each particle is in the three-dimensional space at each time, and draw this in a four-dimensional spacetime, where time is the fourth dimension.
In every instance of the illustration, we see that all of these elements exist still in a four-dimensional pattern. Time doesn't flow, but everything within the boundaries of time moves and so it sort of feels like time is moving to the observer inside that dimension.
Furthermore, things became more complicated when quantum mechanics emerged but according to Tegmark, the math is not entangled in these web of complications. It is "beautiful and clean".
Randomness is fundamentally an illusion because there is no randomness in the math, even though it might feel random. I’m saying the same thing about time. Even though the flow of time is fundamentally an illusion, there is nothing flowing about the math, the equations aren’t changing, there is just a single four-dimensional pattern, albeit a very complicated and beautiful one, in spacetime.
If we were to think about it, Tegmark makes a point. Our perception of time feels like it's lurching forward every second of every hour of every day. But the thing is, time doesn't move at all. We're the ones constantly in motion and perhaps the patterns that exist in nature are merely markers we use in order to keep track of where we are and where we've been.
We mark time simply for our benefit, to make things easier for us to know, say, how productive we have been or to remember certain appointments that we have had. And even that doesn't contradict the concept that time does not flow.
-via The Daily Grail
(Image credit: Andrik Langfield/Unsplash)