timekeeping – Will Johncock

Alex Pasternack describes how timekeeping is the measurement of the passage of a second, which equates to how long it takes for a certain amount of radiation to be given off by a cesium atom in the universe.

The primary aim of timekeeping is to measure the passage of a second. To be precise, that is equivalent to the amount of time it takes for the hyperfine radiation given off by a cesium-133 atom at its ground state as it transitions between energy levels, and its electrons oscillate exactly 9,192,631,770 times.

These days, counting a second depends upon firing a microwave beam at one of these cesium atoms and counting the effect on its electrons. At that scale, the slightest aberration can knock a clock off its count. And then there are the effects of gravity, which Einstein’s theory of special relativity showed can shift the pace of time.

“At the nanosecond level—a billionth of a second—every clock has its own personality,” Matsakis wrote in an email. Each clock will tick faster or slower at certain times, and generally, scientists can correct for this using software. The trickier part is understanding the rate–sometimes sudden, sometimes slow—at which a clock’s ticking may be changing. “We must be on the lookout for deviations from the predicted behavior, and be sure to predict well.”…

“Once I had this definition of time, that it’s a coordinate that you can measure the evolution of in a closed system,” Matsakis said. “Now, I think of time as something that, stripped down to its essence, is a measure of interactions,” an idea based on Einstein’s theory of relativity, which pins time and space to the relative motion of objects. “It’s an intriguing thought: if you don’t have interactions, time is irrelevant.”

He offers an example that begins at the end of time. “One way that time could stop is if the universe could reach a cold death. If our universe expands forever, and the suns die out, and they become black holes which evaporate over eons, what’s left is a rarefied gas, a cold gas that’s uniform across the universe. With everything the same, how can you have time? There’d be nothing to measure time. Time would stop, and not with a bang. It would just peter out.”

The relative interactions that govern the movement of time explain why events in the universe don’t easily fit along a timeline. “Imagine that people witness Al Capone robbing a bank in 1930,” he said. “Then, a supernova a thousand light-years away is observed somewhere on Earth in 1987. Did the star explode first, or was the bank robbery first? It depends on the observer.”

In an email later, I mentioned Nieztsche’s proposal of eternal return. Matsakis shot back: “It is very hard to define fundamental things. I haven’t tried to define ‘place.’ Socrates spent years trying to define justice. Maybe they were right about him corrupting the youth.”

It was Aristotle’s contemporaries who first mastered the calculation of the passage of time, or chronos, and it was they who also recognized another kind of time, kairos—the moments that define our pleasures and our pains and our deepest feelings and thoughts.In other words, the kind of time that can’t be metered by any clock.

Tensions linger between this sense of “time,” which Henri Bergson would later describe as “duration,” and the tick-tocks of “the time” overseen by the timekeepers. Now more than ever before, argues Douglas Rushkoff in Present Shock, distractions keep the latter version of time in a kind of tug of war with the former.

“We spent centuries thinking of hours and seconds as portions of the day,” Rushkoff told David Pescovitz last year, “But a digital second is less a part of a greater minute, and more an absolute duration, hanging there like the number flap on an old digital clock.” The rush of the present and its seemingly infinite, hyperlinked possibilities means “a diminishment of everything that isn’t happening right now—and the onslaught of everything that supposedly is.”

But according to time, not everything is happening at once, as Wheeler joked. Could the Master Clock, I wondered, with its steady, orderly pace, remind us that the world isn’t moving any faster?

But not even this ticking will be the same in the future. With new clocks, the way that time is counted will change. And in time, the definitions of time will change too, if not the questions that endlessly circle it.

“What I tell people is, I can’t tell you what time is,” Matsakis said, “but I can tell you what a second is” (Pasternack 2014).

Pasternack, Alex. 2014. “How the master clock sets the time for the world.” Motherboard, November 7, 2014. https://motherboard.vice.com/en_us/article/ 3dkd5b/demetrios-matsakis-and-the-master-clock

Alan Edwards posits a distinction between natural time, and human constructions of time. Athletes are said to be able to train themselves to measure the relative amounts of humanly constructed time.

Ahh, Sunday is the end of daylight-saving time. Go to bed. Sleep in. Magically gain an hour of time.

Pretty nice, huh? Creation of time ex nihilo with a simple twist of the clock dial.

But wait a minute, you say — that hour didn’t appear out of nowhere. It’s the repayment of a one-hour loan we granted the universe back in April, when we set our clocks one hour ahead. All right — so where has that hour been all this while?

Being as it is an amalgam of nature and artifice, time is a tricky thing. The only natural divisions of time we use are years (the time it takes Earth to orbit the sun), days (one rotation of the Earth) and lunar months (the time it takes the moon to wax and wane). Hours, minutes and seconds are all human constructs…

The only thing that now connects human time with natural time is the year. The Earth’s orbit around the sun is currently measured by the positions of a variety of stars and quasars.

Since an official atomic second is slightly shorter than a “natural” second (it takes about 86,400.002 atomic seconds to fill an average solar day), every so often the Bureau International des Poids et Mesures outside Paris, the official worldwide arbiter of time, inserts a “leap second” into the year to make up the difference.

The Bureau International collects data from dozens of atomic clocks throughout the world, statistically compares them and comes up with an official worldwide time. The Directorate of Time at the Naval Observatory in Washington, D.C., and the National Institute of Standards and Technology in Boulder, Colo., are two of the contributors…

Far from a steady, flowing stream, time is relative: The faster one moves through space, the slower one moves through time and vice versa (and that’s not even taking into account gravitation).

Everyone moves through combined space-time at the speed of light — we humans, moving very slowly through space, make it up through rapid movement in time. Electromagnetic radiation, moving at the speed of light through space, doesn’t move at all through time. For light, time stands still.

But Einstein was right — we experience relative time every day. Numerous studies have shown that people perceive time to pass quickly when they are doing something enjoyable or concentrating hard, while time passes slowly while they’re waiting or bored. Time, in other words, really does fly when you’re having fun.

Relative time is helped by the fact that most humans have lousy internal clocks. Put a person in a room with no stimuli and tell him to call in an hour and he’ll usually miss the mark by a wide margin.

Some people, however, have trained themselves to sense time. An elite athlete, for example, can tell through a thousand tiny signs whether he’s moving fractionally faster or slower. Coaches take advantage of that innate sense with “tempo trainers” — tiny metronomes that sound tones in the athlete’s ear to time his movements.

“It’s a skill that takes a long time to learn,” said Deward Loose, swimming coach at Lone Peak High School in Utah County. “It’s kinesthetic awareness. Call it feel. It’s amazing to me. . . . The elite swimmers can tell the difference in 100ths of seconds.”

Great hitters see the baseball slow down to the point that they can count the stitches. The ball becomes huge for great tennis players. And it’s not only them. “A number of psychological studies have demonstrated that time expansion is well within the reach of common mortals,” said social psychologist Robert Levine.

Thus we can, with enough effort, implement Thomas Mann’s instruction:

“Hold fast the time! Guard it, watch over it, every hour, every minute! . . . Hold every moment sacred. Give each clarity and meaning, each the weight of thine awareness, each its true and due fulfillment” (Edwards 2003).

Edwards, Alan. 2003. ‘Timekeeping has a long, interesting history.’ Deseret news October 23, 2003. https://www.deseretnews.com/article/515040547/Timekeeping-has-a-long-interesting-history.html