Making Sense of Time, Earthbound and Otherwise
By NATALIE ANGIER
January 23, 2007
The New York Times

More than three weeks have passed since the great Waterford disco ball dropped over Times Square, and
most of us are taking 2007 in stride. The time is flying by, just as it does when we’re having fun, approaching
a deadline or taking a standardized test on which our entire future depends, though not, oddly enough, when
we ourselves are flying, especially not when we are seated in the last row, near the bathrooms.

But before we stuff the changing of the annum into the seat pocket in front of us and hope that nobody
notices, it’s worth considering some of the main astral and terrestrial events that make delightful concepts
like “new year” and “another Gary Larson calendar” possible in the first place. Let’s think about the nature of
so-called ordinary time, the seconds, days, seasons and years by which we humans calibrate our clocks and
merrily spend down our lives. As Robert L. Jaffe, a theoretical physicist at M.I.T., explained in an interview
and recent articles in Natural History magazine, our earthly cycles and pacemakers are freakish in their
moderation, very different from the other major chronometers that abound around us, but of which we remain
largely unaware.

The long and short of the universe is just that, almost exclusively long and short, with the hyperclipped
quantum clickings of the atom on one end and the chasmic lollygags and foot drags of the greater cosmos
on the other. We terrestrial, tweener-timed life forms are the real outliers here, the kinky boots at the party.

So what are the public and private rhythms by which we humans abide? Our prima donna of a planet twirls on
its axis once every 24 hours and so gives us our days, and as it rotates it circumnavigates the sun to sketch
out our 365-day years; and because the angle of Earth’s spin relative to the big, flat platter of its orbit isn’t
straight up and down, but instead is tipped by 23 degrees, we have our seasons, our cashmere and cotton,
the heartbreak of clothing moths.

These cycles have been in place at more or less their current configurations since the birth of Earth more
than four billion years ago, and they have set the dials and counters of virtually all life. Every cell of the
human body pulses to a circadian beat, sucking in glucose, squirting out hormones, building up fresh
proteins and breaking down stale ones, all in predictable swells and troughs throughout the day, a
rhythmicity that may help explain why we love music but still does not explain the lingering popularity of
Bachman-Turner Overdrive.

Elsewhere in the solar system are other worlds, taking care of their business, working their quirky times.
Saturn, for example, spins as snappily as it accessorizes, completing a day in 10½ hours; but being almost
10 times farther from the Sun than we are, it needs 30 of our years to finish one of its own. Mercury, by
contrast, orbits the Sun in just 88 days, but rotates a miserly one and a half times during the entire mercurial
“year,” which means that the side facing the sun has a chance to bake to 700 degrees Fahrenheit, while the
half staring out into space turns as cold and miserable as that poor little demotee from the planetary
pantheon, Pluto.

These various blends of diurnal and annual cycles are all perfectly comprehensible, if medically ill-advised.
But just as the light that we humans deem “visible” represents a tiny part of the vast electromagnetic
spectrum, so the collected clocks of the solar system are a meager sampling of the universal stock of
tockers. Far more action is going on below the surface, in the subatomic community. There we find events
occurring in increments far briefer than classic quickies like “in a heartbeat” (i.e., about a second) or “in the
blink of an eye” (a tenth of a second), and down into the realms of scientific notation blessedly leavened with
Marx Brothers nicknames — intervals like the attosecond (a millionth of a trillionth of a second, or 10-18
second), the zeptosecond (a billionth of a trillionth or 10-21 second) and, my personal favorite, the
yoctosecond (a trillionth of a trillionth, or 10-24 second). No matter the nomenclature; the duck soup is ever
astir. The time it takes a quark particle to circle around inside the proton of an atomic nucleus? Midway
between zepto and yocto, or roughly 10-22 second. For an electron to orbit the proton to which it is madly,
electromagnetically attracted? A not-quite-atto-sized 10-16 second.

Fleeting does not mean flaky or unstable, however. To the contrary: the fundamental quivers of the atom
“are exceedingly regular,” Dr. Jaffe said, adding, “They mark the heartbeat of the universe.” Atomic events
are so reliable, so like clockwork in their behavior, that we have started tuning our macroscopic timepieces to
their standards, and our beloved second, once defined as a fraction of a solar day, is now officially linked to
oscillations in a cesium atom.

Or look to the expanding firmaments, the unspeakably protracted pace of the space race. Cosmic time is as
difficult to grasp as the twitchings of the atom, but it, too, is rule bound and reliable. Galaxies and clusters of
galaxies are moving away from one another in defined intervals as the space between them expands like the
rubber skin of an inflating balloon. They have been sailing outward from one another for nearly 14 billion
years, since the staggering, soundless kaboom of the Big Bang set this and all clocks ticking, and they will
continue their dispersal for tens of billions, hundreds of billions of years more.

We are poised between the extremities and homogeneities of nature, between delirium and ad infinitum, and
our andante tempo may be the best, possibly the only pace open to us, or even to life generally. If we
assume that whatever other intelligent beings that may be out there, in whatever alpha, beta or zepto barrio
of the galaxy they may call home, arose through the gradual tragicomic tinkerings of natural selection, then
they may well live lives proportioned much like ours, not too long and not too short. They’re dressed in a
good pair of walking boots and taking it a day at a time. And if you listen closely you can hear them singing
gibberish that sounds like Auld Lang Syne.