Between 1:59 a.m. and 3 a.m. this Sunday, nothing will happen. Nobody will be born. Nobody will die. And practically no one will notice. There won't be enough time

Nothing has happened during those 60 minutes on the last Sunday in April since 1972 because of an act of Congress. Legislation wiped the time clean off the slate to impose a scheme that would better align our waking habits with the sun's slowed motion across the summer sky.

The illustration of a clock that'll appear this weekend on the front pages of most newspapers is a reminder to cram that hour into the few seconds it takes to wrestle the hands of time forward: Go directly past 2 on Sunday morning and on to 3. We've become so accustomed to the idea of daylight saving time that we hardly give the abandoned hour a second's thought.

But when time flies does it fly first class?

Scientists who study time say that depends on who's the pilot, adding that the whys and hows of that shuffled hour suggests a lot about the perception of time in America.

Our cultural way of traveling through daily time, they say, creates real barriers, separating us from much of the rest of the world. The difference is telling: Many other cultures see time so differently that our tinkering with a single hour this weekend seems "meaningless and illogical" to them. They can no more relate to our notions that we can waste, make, run out of, pass, and save time than we can comprehend their seemingly negligent attitude toward time. They say we're artificially regimented to mechanical time. We say they're lazy. They say we don't care about people and nature. We say they're undisciplined and not progressive.

To understand the plight of the hour, it's necessary to accept momentarily the American obsession with precisely measured time.

For centuries, we set our watches according to Sir Isaac Newton's notion of "true and mathematical" time. He believed time was absolute -- as if an imaginary timekeeper somewhere out in the cosmos ticked off the hours and events of each day from here to Jupiter and beyond. Newton can be credited for seeding the mistaken Western notion that all the world sees time identically, but simply in different time zones.

It's typical of the American perception of time, says Edward T. Hall, emeritus professor of anthropology at Northwestern University. "There are serious misconceptions about time," says Hall, who is in Tokyo, where he is continuing his investigation of the cultural differences examined in his book, The Dance of Life: The Other Dimension of Time (Anchor Press/Doubleday, $5.50). "The primary misunderstanding is that time is singular. It's not an immutable constant, as Newton supposed, but a cluster of concepts, events and rhythms covering an extremely wide range of phenomena."

To show the relativity of time, Einstein proved that a clock's measurement depended on its speed as it moved in relation to the speed of light. The average American speeding to get to work on time usually sees that as so much scientific poppycock. But Hall says Einstein's single-handed dismissal of singular time pioneered the notion that "time is what a clock measures" -- and the clock can be anything from the measurement of oscillations of an atom, to a calendar of religious ceremonies, to your stomach at lunchtime, to the spin of the Earth.

Certainly enough evidence has mounted since Einstein to stage a breakout from what James Joyce called "the narrow confines of linear time."

The 15 billion years some scientists claim to be the age of the universe, or to the trillionth of a second that can be measured by the Johns Hopkins University applied science lab, seems to undermine the meaning of an hour.

"It sounds boastful, but the physicist has sort of cleared up the things that take about an hour," says David Park, professor of physics at Williams College in Williamstown, Mass., and former president of the International Society for the Study of Time. "The cutting edge of physics deals with time that is inconceivably short or inconceivably long -- timing elementary particles or the whole cosmos. The hour falls right in between."

Park, the author of The Image of Eternity: Roots of Time in the Physical World, likes to equate one hour (actually 52 minutes) to one-millionth of a century. " Time is a variable scale," he says, "relative to who is talking about it. Time is absolute only in the sense that 'up' is absolute. Everyone in Washington understands the notion of up -- but everyone in Australia understands it differently.

"I think of time as passing. A lot of people think they are standing still like a rock in the middle of a river and time is streaming by them. Back during the Middle Ages, people had the impression that time stopped at night, and started up again when they got up in the morning. When church clocks that struck the hour all night were installed, it was a hell of a discovery for people to realize time was pounding along even when they weren't using it."

Ironically, one bell-ringer that Park says should wake the American perception to the variable nature of time is the exacting science of time itself.

Prior to 1956, the measure of a second -- the basic division of time -- was 1/86,400 of the mean solar day, a figure dependent on the rotation of the Earth. But because the Earth's rotation around its axis is irregular, it was unreliable. The standard was changed to Ephemeris Time, basing its precise measure on astronomical events. In 1967, the second was again redefined. It became the frequency of radiation emitted by a celsium atom as measured by an atomic clock, making today's 'universal' time independent of any Earthly or astronomical motion.

"The National Bureau of Standards knows very beautifully how long a second is," says Park. "But the Earth doesn't know it very well." Because atomic time and Earth time regularly get out of sync, a full "leap second" is occasionally added "to keep noon at noon," he says.

Competing for attention with atomic clocks and Earth clocks is the biological clock we hear so much about. It's a hypothetical mechanism of intuitive and internal timing that scientists have yet to prove conclusively exists. But demonstrations of the biological clock's accuracy continue to suggest it may exceed that of the finest Swiss timepieces.

Pavlov demonstrated first that animals could be conditioned to tell time duration. His laboratory dogs would salivate promptly every 20 minutes in anticipation of their regular feeding.. More recent findings show that African ringdoves will come to blows over punctuality in nest chores, and even bees will reappear at a specific hour and place to gather syrup -- with no external clues, not even the position of the sun.

In humans, some scientists suggest the intrinsic measuring capacity is related to the brain's measure in encephalographic rhythm -- Alpha waves of 10 cycles per second in the brain.

"The stability and accuracy of how well people discriminate time intervals . . . show how finely tuned the internal timeclock can be," says Lorraine Allan, professor of psychology at Canada's McMaster University in Hamilton, Ontario. Allan and her colleagues have documented that people can learn to distinguish between time intervals that differ as little as 1/40th of a second -- with 100 percent accuracy.

A recent study at Queens College of the City University of New York demonstrated that 3- and 4-year-olds somehow can accurately indicate a 15-second time interval time after time with no external help.

But synchronizing with the outside environment is the problem of biological time clocks. Men have spent weeks in caves trying to discover if their internal timing activity is in phase with events that take place outside the body, says Hall.

In one extreme experiment reported by Jugen Aschoff of the Max Planck Institute in Andechs, West Germany, at a 1983 conference on time perception in New York, a volunteer who lived a month in an underground compartment -- with no time reference -- began eating and sleeping according to her own "biological clock." Her schedule naturally shifted to a 52-hour day, although she was unaware it was out of sync with the daily schedule of the outside world.

Yet Hall says that while most people, without some sort of intervention, manage to keep their biological clocks in sync with the external environment, it's that synchronization that most distinguishes perception of time in different cultures.

In the United States and most of Europe, time is perceived in puritanical, "monochronic" terms, says Hall. "These are people who usually do only one thing at a time. There are schedules to tell us what to do when. Time is an outside force helping us to organize our lives.

"In polychronic cultures, time springs from within. The purpose of Zen, for instance, is to attune one's self with nature and to 'eat when hungry and sleep when tired.' "

Monochronic time, says Hall, is arbitrary and learned. And because it is so thoroughly woven into the fabric of monochronic culture, we hardly are aware of the degree to which it determines and coordinates everything -- from social and business life to sex life.

"It enables us to concentrate on one thing at a time," he says, describing an hour for an American as like an empty container waiting to be filled.

"Americans evaluate themselves by those containers," says Hall. "Full is best. Polychronic people seldom experience time as wasted. Their perception emphasizes involvement with people and completing transaction rather than strict adherance to schedules."

While monochronic time may help us compartmentalize our lives into manageable linear operations, Hall warns it also can alienate us from our biological timing. He suggests it could be a factor contributing to much of the stress-related diseases and tension that attack Americans and Northern Europeans -- but not many polychronic cultures.

"Isn't it strange that an hour of daylight saving time that makes a big difference in our lives wouldn't make any difference in some other cultures?" says Hall. "We get very excited over a small change in time. A polychronic person would be mystified by it. We feed the baby on schedule. Polychronic people feed the baby when it's hungry, when the internal clock says it's time to eat."

Arabs, American Indians and South Americans tend to be polychronic. They can typically take on several activities at at time, says Hall, using the example of Middle Eastern souks, where noisy customers all vie for the attention of a single clerk who is trying to wait on everyone at once. He mentions the Quiche' Mayans of Guatemala whose complex perception of time has nothing to do with dividing the day into equal parts but instead living each day in the most proper way. He points to the South American businessman who invariably is late for appointments.

In a recent comparative study of American and Brazilian perception of what is considered late for an appointment, Robert Levine, professor of psychology at California State University, Fresno, found the average Brazilian student defined just over 33 minutes as late, while the average California student said 19 minutes. Levine, who reported the findings in Psychology Today, said a majority of Brazilian students believed a person who is regularly late is probably more successful than someone consistently on time.

"Matters in polychronic cultures seem in a constant state of flux," Hall says. "Nothing is solid or firm . . . even important plans may be changed right up to the last minute . . . it looks like confusion."

Hall, who lives in Sante Fe, N.M., adds that you don't have to leave the United States to find conflict of time perceptions. The Hopi and Sioux Indian tribes, among others, he says, have no word for time in their vocabulary.

Instead, they live in the eternal present, where "time is not the harsh taskmaster," he explains, "nor is it equated with money and progress . . . For them , the experience of time must be more natural, like breathing."

Howard Rainer, assistant director of American Indian Services at Brigham Young University, is a Taos Pueblo Indian who says that for Native Americans, "nonadherence to the white man's rigid time schedule is one of the last strongholds of cultural resistance to succumbing to total American inculturation."

Working with young Indians who inevitably "drag in at their own leisure" to scheduled appointments and classes, Rainer says he regularly witnesses "a constant conflict of cultural values of opposing forces.

"Many Indian people connote the white man's value of time as a way of gaining wealth, prestige and power," says Rainer. "They feel white people are racing through life, watching their time. The Indian recognizes time in the seasons. They tie the relationship with Mother Earth and her changing seasons. It's a frustrating thing. You try to function in two worlds."

What about the lost hour of daylight savings time for the native American?

"It's illogical," says Rainer. "Many people in this world respond to the sunrise and the sunset. They don't have to look at a clock and say 'Oh, it's 8 o'clock, we gotta get up.' For the Indian, time is all around him. For the white man, you strap it on your wrist and live by it."