For three years and 50 weeks at a stretch, hundredths of seconds are irrelevant. They are the arcane province of those physicists and mathematicians who seemingly take delight in anything that makes the world more complicated. Then the Olympics arrive, and the rest of us understand.
When Justin Gatlin's every muscle ripples into a wave of kinetic perfection, a hundredth of a second becomes a Cézanne still life in three dimensions - a living moment impossible in its brevity and beauty. When Michael Phelps wrenches toward the wall in the violent grace of his butterfly stroke, 0.04 seconds is an instant that expands into generations of renown.
For a nation that measures athletic success almost exclusively by goals, points, and runs, these two weeks reacquaint America with the fingernail finish. This year, some of the most anticipated Olympic events have been decided by a hiccup of the stopwatch. And the evidence points to photo finishes only becoming more common.
As more nations compete - and compete well - in the Olympics, the space between each competitor has narrowed. Now, world-class swimmers and sprinters come from every corner of the globe, pressing the traditional winners - and compacting more races into an anarchy of equality.
"There are more athletes who compete at a high level," says David Wallechinsky, a historian whose book "The Complete Book of the Summer Olympics" chronicles every race in Olympic history. "They've always had the potential."
He credits not only increased participation - a record 202 nations are represented at these Games - but also improved training techniques. The trend has brought along talent from developing countries, such as Nigerian 100-meter silver medalist Francis Obikwelu, who now trains in Portugal and represents that country.
It can also bring along talent in the United States, where fourth-place finisher Shawn Crawford was known as a gifted but undisciplined runner before he hired Trevor Graham - who also coaches Gatlin.
The result was, by many measures, the closest and fastest in Olympic history. In any other Olympics, Crawford's 9.89 seconds would have won him at least a silver. Sunday night, he finished fourth.
In fact, the margin between first and fourth place - 0.04 seconds - was probably the smallest in Olympic 100-meter history. The 1952 race is the only one that comes close, but officials timed that event only to tenths of seconds.
These days, it seems, a tenth of a second is enough time to cook breakfast and hand-squeeze the orange juice. When the US men's swimming team for the 4x100 medley relay toppled the world record by 0.86 seconds last Saturday night, the margin was considered massive - the work of a dream team that included current world-record holders in the backstroke, butterfly, and breast stroke.
By contrast, just 28 years ago in Montreal, the American 4x100 medley relay team bested the world record by nearly six seconds. The days when relay teams would win events by 10 seconds or more - which was routine during the first 40 years of the modern Games - now seems a stone age when swimmers wore beaver pelts instead of Speedos.
"We are not as dominant as we used to be," says Aaron Peirsol, who swam the relay and holds the world record in the 200-meter back. "It's not because we aren't as good; the rest of the world is catching up."
That may weaken American dominance in sports where hundredths of a second often matter the most - swimming and sprinting. But it puts the Games on the knife edge of excitement, when the energy of anticipation swells in those few moments between the end of a performance and the certainty of who won.
Stateside, few mass-appeal events - perhaps NASCAR and horse racing - offer any approximation of that sensation. And there, the competitors are just along for the ride, in a sense. Here, the drama is purely human, and it unfolds nightly - with years of preparation, and a potential lifetime of fame, hanging in the balance of a few uncertain seconds.
Phelps touched the wall after his last-second surge in the 100-meter butterfly not knowing whether he had caught teammate Ian Crocker. Paul Hamm stood transfixed, waiting to see if his flip off the high bar was enough for the complex calculations of gymnastics judging to make him an Olympic champion.
On the scoreboard that night, 0.012 points made the difference - the smallest margin in Olympic history for that event. Tuesday, as judges admit that they made a scoring error that took the gold from a Korean, two countries are in an uproar over a tenth of a point.
America is the nation that invented Arena Football because the NFL's 40-point games just weren't exciting enough. Only the Olympics could make a tenth of a point more exciting than a touchdown.
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