A Timeless Question: Just When Did Time Really Begin?

On New Year’s Eve, my daughter and I were trying to decide whether to bring in 1997 at midnight Pacific time, or midnight in New York, when the ball dropped at Times Square--or whether, indeed, it made any difference.

And then she asked me: So when did time begin, anyway?

Beginnings, it turns out, pose some of the juiciest questions in all of science.

Consider 1997, for example. When did it begin? When people in New York raised their glasses? People in Tokyo? Siberia? Imagine you could look at Earth from space and watch the new year begin in one time zone after another around the world until the circle was finally complete and it was 1997 everywhere.

But what about the first year ever? When, exactly, was that?

Given that a year marks one complete orbit of the Earth around the sun, we have to assume that the “year” was born only after the solar system was established.

When exactly did the clump we now call Earth grow big enough to settle down into a stable orbit, and thus carve out its first year? Pinning a date on that is problematic at best.

The same is true for the first day. Since the day marks a single rotation of the Earth around its axis, Day One took place when Earth began to spin. But the clumps of dust and rock that made the Earth had some spin before they joined together. And new spinning chunks (like comets) add their spin to Earth every day.

One thing we know for sure is that the early Earth rotated a great deal faster than it does today, so that Day One, whenever it was, was a whole lot shorter than Jan. 1, 1997. As recently as 900 million years ago, the length of a day on Earth was only about 18 hours.

Of course, one could argue that it makes no sense to talk about days and years until humans first noticed that patterns of light and darkness fell upon the Earth in regular rhythms, that seasons came and went like tides. When did life become sufficiently conscious to ponder beginnings? Did conscious thought begin with people? If so, when did humanity begin? When did life begin?

These questions are so controversial that a dozen researchers might well give you a dozen (or more) different answers. Curiously, there are also beginnings to things we take for granted as having been around forever. Death, for example.

University of Massachusetts biologist Lynn Margulis has argued that single-celled creatures don’t really ever die, because they procreate by dividing in two. They literally live on in their offspring. Only when living things began to reproduce themselves sexually did death of the individual begin. Death, Margulis says, is the price we pay for sex.

Matter, also, has a history. When the universe was formed 15 billion years or so ago, space was filled with energy that cooled into quarks and other elementary particles. However, energy is an equal opportunity employer, and for every bit of matter created there was also a bit of anti-matter. When matter and anti-matter meet, they annihilate each other in a burst of pure energy.

In fact, no speck of matter would exist today if it hadn’t been for a slight imbalance in the proportions of matter and anti-matter in the early universe. Just how and when that imbalance began is a question that torments physicists.

Energy itself began with the big bang--the primordial explosion that set off the universe, life . . . everything. But when, exactly, did the bang begin?

The question can’t really be answered--except to say, perhaps, that it began at the beginning. Since there was no time or space before the universe began, time itself was born along with the universe. The universe began at time zero. No time before is imaginable.

If you find that hard to get a handle on, physicist Stephen Hawking suggests you try to imagine what’s “north” of the north pole. There’s no there there.

Or as the poet Octavia Paz put it: “The great lesson of modern science is that . . . questions about the origin and the end are the most important ones.”