Time may not exist at all, as it turns out. We’re seeing an illusion. Sorta, at least within quantum mechanics. Time is still real enough on the macro-scopic level.

“One finds that time just disappears from the Wheeler-DeWitt equation,” says Carlo Rovelli, a physicist at the University of the Mediterranean in Marseille, France. “It is an issue that many theorists have puzzled about. It may be that the best way to think about quantum reality is to give up the notion of time – that the fundamental description of the universe must be timeless.”


Einstein’s proved that the speed of light is constant and time was relative to the observer. 19th century scientists believed light traveled through ether and observes could measure changes in the speed of light as their own velocity changes. That would be expected of sound or wind. But light speed is an absolute constant of the universe. Under Special Relativity both space and time change – there is time dilation and space contraction.

Admittingly, Relativity is not something I grasp. The real logic of it comes from mathematical formulas rather than verbal descriptions.

But even Krausz works far from the frontier of time. There is a temporal realm called the Planck scale, where even attoseconds drag by like eons. It marks the edge of known physics, a region where distances and intervals are so short that the very concepts of time and space start to break down. Planck time—the smallest unit of time that has any physical meaning—is 10-43 second, less than a trillionth of a trillionth of an attosecond. Beyond that? Tempus incognito. At least for now.

Efforts to understand time below the Planck scale have led to an exceedingly strange juncture in physics. The problem, in brief, is that time may not exist at the most fundamental level of physical reality. If so, then what is time?

Rovelli offers his guess.

Rovelli, the advocate of a timeless universe, says the NIST timekeepers have it right. Moreover, their point of view is consistent with the Wheeler-DeWitt equation. “We never really see time,” he says. “We see only clocks. If you say this object moves, what you really mean is that this object is here when the hand of your clock is here, and so on. We say we measure time with clocks, but we see only the hands of the clocks, not time itself. And the hands of a clock are a physical variable like any other. So in a sense we cheat because what we really observe are physical variables as a function of other physical variables, but we represent that as if everything is evolving in time.

“What happens with the Wheeler-DeWitt equation is that we have to stop playing this game. Instead of introducing this fictitious variable—time, which itself is not observable—we should just describe how the variables are related to one another. The question is, Is time a fundamental property of reality or just the macroscopic appearance of things? I would say it’s only a macroscopic effect. It’s something that emerges only for big things.”

Due to many complex interactions, something like of time appears to measure spatial displacement. How do you measure an object’s movement from point A to point B? By the time it takes. But at the smallest level, time may not matter.

Then they go into Quantum Mechanics. That has something to do with that damn dead cat. But again, the only way to understand this is through mathematical formulas. Otherwise you listen to the dead cat story and have no idea what’s going on.

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