We all instinctively know that time and space are not things – the kind of objects that you can see, feel, taste, touch, or smell. There is a peculiar intangibility about them.

The makers of the world’s most precise clocks – atomic clocks – are among the greatest appreciators of time’s mysterious nature. “Time has a mystique for all of us. We have rulers to measure it, but to describe it? That is another thing,” said Dr. Leo Holberg in a recent interview. He is one of the leading physicists at the National Institute for Standards and Technology (NIST), in the Time and Frequency Division in Boulder and this week’s Pinhead Town Talk presenter. “Time: A Modern Perspective from a Builder of Atomic Clocks,” will be held on July 17, at the Conference Center in Mountain Village from 6:00-7:15 p.m. Admission is free and there will be a cash bar.

In a rare Pinhead Town Talk presentation, Holberg will dare to cross the boundary of science into philosophy, while clearing delineating the science and history behind modern time keeping. Echoing the thoughts of Plato, Holberg says that time is related to motion, the difference in spatial position of things. “If things stopped moving, there would be no time.”

Pondering whether or not time is “real” or simply the comparison of periodic, dynamic relationships, he answered, “Time is real for us. Our hearts beat and our blood flows. Our senses perceive motion and we experience it as time. We see a pencil fall; there is an interval before it hits the ground. We perceive this as time.”

The human obsession with measuring and understanding time is well documented. It has been a philosophic, religious, and scientific process existing throughout cultures and throughout the ages. Author David Ewing Duncan wrote in his 1998 international bestselling nonfiction book, Calendar: “For thousands of years, the effort to measure time and to create a workable calendar was one of the great struggles of humanity, a conundrum for astronomers, mathematicians, priests, kings, and anyone else . . . A case can be made that science itself was first sparked by a human compulsion to comprehend the passing of time, to wrestle down the forward motion of life and impose on it some sense of order.”

From the early power struggles to standardize a calendar came the desire to perfect the clock. The most accurate clock today is the rather romantically named, atomic “fountain clock.” Unlike clocks of old (sundials, water clocks, candle clocks, grandfather clocks, pendulum clocks, which were adequate for measuring seconds, minutes, and hours) cesium atomic clocks can actually detect the variations in the earth’s rotations and revolution in tiny increments called picoseconds (one billionth of a second) and femtoseconds (a quadrillionth of a second). Cesium frequency standards are much more reliable and reproducible than the rate of rotation of the earth. (Cesium is a rare chemical element of the alkali metals group that is the most reactive of the elements.) But atoms, which are the equivalent of the quartz crystal in a watch or the master pendulum in a clock, operate on a different scale than the macroscopic world, and therefore are naturally out of sync with the cosmos.

“How does the atomic clock relate to the calendar? It’s a bit of a problem,” Holberg said on the phone from NIST. “Historically calendars were driven by the rotation of the earth relative to the stars, months by moons, all modified over the years by kings, popes, and parliaments. But the Earth’s rotation is not uniform. The earth’s rotation slows down because of friction caused by things like tides, earthquakes, and volcanoes. The Earth wobbles. Earthquakes can change the rate of the Earth’s spin, for example.” The earthquake in Indonesia that caused the Tsunami sped up the rotation of the Earth. The Earth is now is the process of slowing down, and the year 2007 will be shorter than 2008. Earthquakes do not always sped up the Earth, they can conversely slow it down.

This discrepancy between cosmic and atomic measuring systems is caused, in part, because atoms don’t experience tides or earthquakes; they don’t experience friction.

We as a society have a decision to make. Do we keep time by synchronizing with the stars or synchronizing with atoms? “If we choose only to synchronize with atoms, noon will eventually drift into darkness of night,” said Holberg. “It would take a long time, but that would be weird.” So the keepers of the world’s atomic clocks, led by The International Bureau of Weights and Measures in Sèvres, France, not only coordinate international atomic time among leading institutions in the US, Germany and France, but periodically, to keep noon at high noon, sync the atomic clocks with the naturally wobbly rhythms of our planet and stars. These comparisons are taken monthly and published. The “paper” result is referred to as the “globally averaged mean time.”

Many applications of science and technology today demand all the precision that the best atomic clocks can provide. “Two primary forces, navigation and communication, have historically driven the keeping of better time. They still do today,” says Holberg. Cell phone, GPS, and TV stations all use atomic clocks. There are 24 satellites in orbit, each with four atomic clocks that run the military’s GPS systems.

“Atomic clocks are so accurate that in 100 million years it might make a small mistake (not that the clock itself will last that long),” says Holberg.” But that has not stopped scientists from trying to keep even better time, to become even more prscise.

Dr. Leo Holberg and Dr. James Bergquist led the recent “International Conference on Laser Spectroscopy (ICOLS)” held in Telluride June 25-29 with 180 international physicists, including three Nobel Laureates. The meeting was organized by the Telluride Science Research Center (TSRC). Holberg is a happy to have a chance to return to Telluride and share his deep understanding and musings with locals and visitors.

The Pinhead Town Talk summer science lecture series is held in partnership with the Telluride Science Research Center and is sponsored by the Town of Mountain village.

Increasingly, time is used to define distance.

Why there are things that can be described as psychological time, is difficult to know. Why does time move much more slowly when we are children than what we experience as adults?

We cannot pick them up and put them on a shelf, like shells or stones found along a seashore. A physicist cannot bring back space or time to the laboratory in a marmalade jar, like a kid brings home lightning bugs, or in a vial, as an entomologist collects insects to be examined, measured, and classified. There is something oddly different about them. In fact, one is used to measure the other.

We all live on the edge of time. That’s a rather comfortable place, really, because it means we are still among the living. On the edge of time, tomorrow hasn’t happened. Our future has not been played out. Most of our descendents haven’t been born. Everything to come is a big mystery, a big void. Our life is ahead of us. We’re out in front, strapped to the engine of the Time Train, which relentlessly travels forward into an unknown future. Everything behind us, so to speak, is the dining car, business class, coach, the latrines, the cattle cars, the boxcars, the mail cars, the caboose, and miles of track we can’t retrace. Everything before this exact moment in time is part of the history of the universe. The vast majority of our ancestors, about whom we know direly litte, are dead and gone. Everything before this moment is the past, gone forever. Or so we think.

But, are time’s arrow and the edge of time a persistent illusions? It is a trick of nature that one calendar day follows upon another, that spring precedes summer, and that years pass.

Let’s think for a minute about time flowing forward into the future and how extraordinary it is that we are here, alive, for a split instant, on the edge of all time. Imagine all the days and hours that have passed since the beginning of time. Now stack time, like chairs, on top of each other, and seat yourself on the very top, or – if you’re afraid of heights and prefer speed – strap yourself once again to the front of the Time Train.

But you know what is interesting? Science has no real explanation for why we're here, why we’re alive now, or why we exist on the edge of time. It's just an accident, a one-in-a-gazillion chance that you are here, alive. The statistical probability of being on top or in front of time is so small as to be meaningless. Yet this is generally how the human mind conceives time. And it is a persistent perception promoted by science and our everyday human experience.

In classical science, humans place all things in time and space on a continuum. The universe is 15 to 20 billion years old; the earth five or six. Upon the planet earth, dinosaurs went extinct 65 million years ago. Homo erectus appeared four million years ago, but took three and half million years to discover fire, and another 490,000 years to invent agriculture. Galileo discovered that the earth revolved around the sun 400 years ago and Newton discovered the universal force of gravity in the 1600s. Darwin discovered evolution in the mid 1800s in the Galapagos Islands. Einstein developed the theory of special relativity in a Swiss patent office in 1905. In the year 2000, the first map of the human genome was drafted in the laboratories of Celera and academic outposts of the Human Genome Project. Ad infinitum.

Time, in a mechanistic universe (as described by Newton and Einstein and Darwin), is an arrow upon which events are notched. We are used to thinking of time as a forward moving continuum, flowing always into the future, accumulating, because human beings and other animals are constitutional materialists; hard-wired, designed, to think linearly.

Call it “day-to-day time”: paying the bills so the gas doesn’t get turned off, the keeping of one’s appointments, the feeding of family and pets, and the deadlines of work.

“Time is related to motion, which is related to light, which is related to relativity. It is natural to compare things to the fastest thing we know, the speed of light.”

Saxons in Britain divided days according to the tides, “morning tide,” noontide,” and “evening tide.”

Ancient Greek Historian Herodotus strung stories together linearly with no documentation of when events took place.

Augustine wrote, “The world was not created in time, but together with time.”

Before the concept of minutes, there was a loose concept of hours, which were then larger fractions of the day.

Calling in from NIST (National Institute of Standards and Technology,” Leo Holberg, a physicist in their Time and Frequency Division in Boulder, Colorado, quipped, “There’s no good time here.”

Main point, “Give the audience a flare for how we keep time. Why we care and who uses it. How does it impact the individual.

A femtosecond is a quadrillionth of a second. Precise timing plays a role in everyday life. How do physicists thing about time. There is biological time, psychological time, and there is the oscillating atom. How does an atomic clock work?

Give an introduction about early clocks, how good were they? Driving forces for keeping time are societal. Meeting the needs of commerce, navigation and communication.

When developing modern GPS systems, the military didn’t believe in relativity. They were proven wrong by physicists who had predicted that time had to be adjusted according to Einstein’s theories of relativity. Time moves faster at higher elevation. Time runs about 30 millionths of a second per year faster at the top of Mount Eerest than it does at sea level” “ Military is the most stringent user of exact time.”

Old clocks = natural, macroscopic event – daily rotation of the earth. Orbital motion of the earth in the solar system is more uniform tha n the solar day. More stable is the year.

There are three primary time scales. Military run GPS time. Then there’s International atomic time. Also coordinated universal time. Is time real? “Time is related to motion, the difference of position of things. If things stopped moving, there would be no time.”

“Time is related to motion, which is related to light, which is related to relativity.” “It is natural to compare things to the fastest thing we know, the speed of light.”

Time has a mystique for all of us. We have rulers to measure it, but to describe it is another thing. I believe that time is real for us. Our hearts beat and our blood flows. We experience motion. Time is a very real thing. Our senses perceive motion and experience it as time. Why there are things that can be described as psychological time, is difficult to know. Why does time move much more slowly when we are children than what we experience as adults?

Time and space coordinates get distorted as you move faster.

Year as measured in oscillations of atomic cesium :
290,091,200,500,000,000

In 1972, atomic time replaced Earth time as the official time standard.

Frances Bacon: Time is the greatest innovator.

Light travels at a very finite, but very high speed.

Stephen Hawking, “We must accept that tie is not completely separate from and independent of space . . . “ A Brief History of Time.

It is impossible to meditate on time . . . without an overwhelming emotion at the limitations of human intelligence.”

The idea of god existing outside of time.

“As important as ‘time’ might be to those who are navigators, scientists, or even musicians, it is no more than an arbitrary parameter that is used to describe dynamics or the mechanics of motion.” Co-author on a NIST paper published in science in 2004, and a colleague of Holberg’s, Dr. James Bergquist.”It is through the external or internal periodic dynamics of one object that we define time, and armed with that time scale, we can characterize the dynamics of other objects – an oddly circular argument.”

Atomic clocks
Three most important standards are stability, reproducibility, and accuracy.

July 13, 2007
Contact Nana Naisbitt, Executive Director
Telluride Science Research Center
970-708-0004 cell