Ironically, the times the world community has responded to the question, “What time is it?” have changed dramatically over time. Knowing what time it is, has been driven mainly by technological needs and advancements. We will see enormous religious implications to what time it is! We read, “…there should be time no longer (Rev. 10:6).”

Traditionally, time has been kept astronomically. Ironically, the invention of atomic clocks has driven the advancement astronomically! In my lifetime, timekeeping accuracy has moved forward an amazing billion-fold. Historically, the agrarian world cared more about the seasons than about what time it was.

First Atomic Clock

Harold Lyon’s ammonia MASER was the first atomic clock (1949). I went to work at the National Bureau of Standards (NBS) in Boulder, Colorado, in 1960. The physics of the ammonia maser is fascinating, and NBS had one I got to work on. After the invention of the maser, Charles Townes went on to invent the LASER (Light Amplification by Stimulated Emission of Radiation). Can you imagine how many LASER scanners there are across the world, considering there is one at every store’s checkout stand? These most useful devices come from the physics of timekeeping!

Pendulum Clock

Galileo used his heartbeat to measure the period of a swinging chandelier in the cathedral in Pizza, Italy. There is a baptism by immersion font in that same cathedral. (We have been there). From those heartbeat measurements, Galileo deduced some interesting laws of physics—preceding Newton. The pendulum clock was invented by Christiaan Huygens in 1656. It became the world’s standard timekeeper, used in homes and offices for 270 years.

Timekeeping World Changed

The timekeeping world changed dramatically in 1735 with John Harrison’s invention of a marine chronometer. (See Dava Sobel’s LONGITUDE). With Harrison’s chronometer, mariners could determine accurate longitude, which was essential for accurate sea navigation, as the Earth spins under the heavens.

This chronometer gave significant superiority to the English Navy. In 1833, the famous Greenwich Observatory time ball was installed. Thus, the ships at port in London could see to synchronize their chronometers before they went out to sea!

The National Bureau of Standards (NBS) in Washington D.C. started broadcasting the time in 1919 from radio station WWV. They used a precision pendulum chronometer and got the correct time from the nearby United States Naval Observatory (USNO). Then, Quartz clocks were invented in the 1930s with significantly superior timekeeping ability. These were the main timekeepers until the invention of atomic clocks.

Idea of the Atomic Clock

In the 1940s, Nobel Prize winner, Isador Isaac Rabi is credited with the idea of an atomic clock. One can think of the oscillating frequency of a photon coming from an atomic transition in an atom or molecule. We add up the oscillations of these photons and make an atomic clock.

The time and frequency Rabi award was named after him. In 1983, he was the first recipient. I was privileged to have breakfast with him on the day of the award ceremony in Philadelphia. I was greatly honored to be the second recipient a year later.

Atomic Time Generated

If you are going to replace the spinning and orbiting Earth as a clock, then that clock needs to never stop. Keeping atomic clocks running continuously is no small matter. Continuous atomic time was first generated by Louis Essen and Jack Parry at the National Physical Laboratory in Teddington, England. So, in June 1955 atomic timekeeping had its birth in the world at NPL using a transition in cesium. The cesium transition was much more accurate than Lyons’ ammonia maser. Lyons went on to build the world’s first cesium-beam frequency standard, NBS-1, in 1952, but he never turned it into a clock.

 Move To Boulder, Colorado

In 1954, the National Bureau of Standards (NBS) was moved to new laboratories in Boulder, Colorado. You can see Roger Beehler working with NBS-1 in this link: https://www.nist.gov/pml/time-and-frequency-division/time-services/brief-history-atomic-clocks-nist. You can see all the rest of the NBS/NIST cesium-beam standards up to NIST-7. In contrast to astronomical phenomena, atomic frequency standards have gotten ten times better about every seven years.

The square root of the Allan variance can be written in a form that gives an estimate of how stable and accurate an atomic frequency standard can be: σ y (τ) = Δν/(ν Signal to Noise). The fractional frequency is defined as y = (v(t) – vo)/vo, vo is the nominal frequency of the transition of interest. If ν(t) is exactly on frequency, then y(t) is zero. But that rarely happens. The atomic transition line width is denoted by Δν. The Signal/Noise improves as Nτ, where N is the number of atoms or molecules interrogated per second, and τ is the time over which y(t) is averaged.

One can see from this equation, that as the transition frequency line width, Δν, improves the stability and accuracy potentially improve. The longer the atoms or molecules can be interrogated, the smaller is  Δν. In a cesium-beam atomic clock, the atoms can only be observed for a few milliseconds. When the cesium fountain was invented, the observation time went up to nearly a second, and the accuracies and frequency stabilities achieved improved greatly as well.

One can also clearly see from this equation that the higher the atomic transition frequency the better can be the accuracy and frequency stability. The cesium transition is a microwave frequency. By going to optical and ultraviolet frequencies great advances have been achieved in accuracy and frequency stability. These frequencies are about 100,000 times higher than the cesium microwave transition. In my career time, atomic clock accuracies have improved from 10^-10 to 10^-18; that is a hundred-million-fold improvement.

GPS is One Example

AMAZING. Many Nobel Prize winners have contributed to these incredible advancements in timing technology. Technology has benefited enormously as well. GPS is one great example. The current best atomic clocks are 10,000 times better than are needed for GPS. GPS timing works at the nanosecond level–that is a billionth of a second. That is the time it takes light to travel 30 cm (about a foot per nanosecond).

Official Atomic Time in USA

Since 9 October 1957 NBS in Boulder, CO has maintained an atomic time scale, (NBS-A). The primary cesium-beam frequency standard moved to Boulder in 1954, but time was broadcast from WWV in Beltsville, Maryland. WWV then had a precision quartz-crystal clock and was still getting its time from USNO.

A Millionth of a Second

On 24 April 1963, Jim Barnes and Lowell Fey carried a portable quartz-crystal-oscillator clock from Boulder to Beltsville, Maryland, and back with a precision of 5 µs (A microsecond is a millionth of a second). Then, timekeeping commenced in Boulder using an ensemble of precision quartz-crystal oscillators. Their portable clock trip took NBS-A time to Boulder, and the primary frequency standard was just across the hall. This gave an accuracy for NBS-A to ten significant digits. This was ten times better than the Earth as a clock.

Generating Official Time for the U.S.

Jim Barnes then wrote the first atomic-clock time-scale algorithm program to use the calibrations from the cesium-beam atomic frequency standard across the hall. He then used the calibrated quartz-clock ensemble to carry time forward until the next calibration. When Jim became the Section Chief, I was given the responsibility for generating official time for the United States. I did that for most of my 32 years we lived in Boulder, Colorado.

Algorithm, AT-1 Still Ticking

I believe the Lord gave me the algorithm, AT-1, in 1968, for generating official time for the USA. Then we had an ensemble of eight atomic clocks and the US primary frequency standard to work with. The AT-1 algorithm optimally combines the readings taken from an atomic clock ensemble. The computed output of that algorithm is designed to be better than the best clock in the ensemble. Significant improvements have been made to AT1 by my outstanding colleagues and friends over the years. New and different kinds of clocks have been added with their own challenges and improved performance differences.

With those improvements, as far as I know, AT-1 is “still ticking” today. In 2018, I received the IEEE $10,000 Keithley Award, “For leadership in time determination and precise timing instruments.” I thank the Lord for His help in this work. It has been most insightful and enjoyable.

A Two-Part Device

For human-kind of timing, we can think of a clock as a two-part device. First, a clock has a periodic event device that oscillates at a steady frequency. Second, it has a counter to count those oscillations. For example, most wristwatches and clocks today use a quartz-crystal tuning fork as the oscillator or periodic event device. It oscillates at 32,768 Hz (cycles per second). A 2^15 binary divider is then used to generate one-second intervals, which are then counted to give you a display of hours, minutes, and seconds for your clock or wristwatch.

When measured precisely, we know that every clock is oscillating at the wrong rate and its time is in error. The only clock that is right is the one we define to be right. For the USA, it is UTC(NIST). For the world, it is UTC (Universal Time Coordinated.) Official world time used to be Greenwich Mean Time (GMT). The name was changed from GMT to UTC in 1972, with the introduction of “leap-seconds” as needed to chase the earth’s fluctuations in time.

A Momentous Day for Timekeeping

Friday the 13th of October, 1967, was a momentous day for timekeeping. The world community shifted from astronomical timekeeping to atomic clocks for keeping time. Atomic clocks have been shown to be much more accurate than any astronomical phenomena. And as mentioned before, atomic clocks have improved by a factor of ten about every seven years. This is like Moore’s law. Today, accuracies of 0.1 picoseconds per day are realized. This is ten thousand times better than is needed for the atomic clocks in GPS. A picosecond is a million-millionth of a second.

A New Definition of The Second

On that day in 1967 the world received a new definition of the second. It is defined as, “9 192 631 770 periods of the ground-state hyperfine transitions of cesium-133.” The previous definition was the Ephemeris second, which is defined by the Earth’s motion around the sun, as well as lunar motion. It is better than a second for timekeeping purposes. The above oscillation frequency for cesium was arrived at by the Paris Observatory, the Greenwich Observatory, and the United States Naval Observatory. The astronomers involved were Bernard Guenot, Humphrey Smith, and William Markowitz, respectively.

I was privileged to know all three of these gentlemen. The 9 192 631 770 periods agreed with the Ephemeris second, as these three gentlemen determined. The cesium definition remains today. With the high accuracies that have now been achieved in atomic clocks, a new definition is a major topic among the scientists involved.

What is Time?

“What Time is it?” is a very different question than, “What is Time?” The most important “time” is God’s TIME. Yet, most don’t have a clue what God’s TIME is. I explain God’s TIME in my two books: It’s About Time and Time & Eternity, The End-Times & Beyond Revealed,” as best I can. Here, I have discussed “time” as generated by humans. In my books, I discuss its relationship to God’s calendars and His TIME. I also discuss what the Apostle John means, “time no longer (Rev. 10:6).” The concept of God’s “One Eternal Round” is profound as well. This is a fun trip through understanding what time is and what time isn’t. Perhaps for more fun for the academics across the world than for my Christian compatriots. But, knowing where we are in God’s TIME should be very important to my academic friends as well.

Time is Metaphysical

It is important to know that time cannot be extracted from the Universe; it is metaphysical. It is an idea in our minds. My dear friend, emeritus professor of philosophy, Chauncey C. Riddle, has the best definition of time that I have seen. He shares, “Time seems to be the possibility of change.” This was particularly interesting to me, because in my master’s thesis, the metric developed optimally measures the change, in a variance sense, in the timekeeping rate of atomic clocks. The world knows it as the “Allan variance.”

As I Google the “Allan variance,” today I got 3,550,000 results, and the usefulness continues to grow. I believe the Lord inspired me in this as well. In 2016, the IEEE/UFFC celebrated the 50th Anniversary of the publication of my thesis. They published a special issue with 16 different papers highlighting different uses of the Allan variance.

At the conference, they gave me the highest IEEE/UFFC award with the citation, “For seminal work to the UFFF community regarding time determination, time prediction, time dissemination and timekeeping through contributions to atomic frequency standards, space-based navigation, time and frequency stability analysis, time-scale algorithms, and timekeeping devices.”

Time Is Not Time

So, time, as we use it and define it, is not time, but a time interval. Scientists assume time runs uniformly throughout the Universe—including Einstein’s relativistic considerations. We contracted with Professor Neil Ashby to do the relativity equations needed for GPS. We are good friends and have written several papers together. Scientists share nothing of time-warp events, which have been documented. We know from our UFT experiments that time and space are mortal limitations. The scientist’s assumption above is incorrect.

God’s Physics

In God’s physics, we learned of a fifth dimension outside the four relativistic dimensions of time and space. We call it the Eternity Domain. This is where God and His angels do their work in the Kingdom of Heaven. Under God’s direction, the Kingdom of Heaven is perfectly organized. That is why the Lord asks us to pray, “Thy Kingdom come, thy will be done on earth as it is in heaven.” Sincere prayer takes us into the “Eternity Domain” where we may learn the TRUTHS of GOD and help bring heaven on earth!

Where Are We in God’s Time?

A significant portion of both of my books deals with where we are in God’s TIME. Please go there to learn what I have learned about God’s TIME. Knowing God’s TIME and preparing for eternity is the most important thing we can do and help others to do. Most of my energies are spent in this direction. I ask the question of the Lord, “What is Thy will to best help me to serve today?”

The Lord never directs every step in our lives. Given the incredibly important gift of free choice, which is part of our intelligence, He wants us to think for ourselves. TO THINK! That sounds exciting. We grow emotionally, physically, mentally, and spiritually in that Divinely designed process of using our agency to use our time and talents to serve.

THINK – LEARN – SERVE – LOVE!!!

“Seek learning even by study and also by faith (D&C 109:7).” To think and learn the TRUTHS of God that we may better love (Matt. 22:36-40) and serve (Mosiah 2:17). My personal joke is to learn faster than I forget! THINK and LEARN and SERVE and LOVE!!! Therein is the greatest joy in time and eternity. Wise men sought for and found the Savior of the World anciently. Wise humans today are doing the same.

One who thinks comes to Christ in humility. There he/she enjoys the fruits of faith, repentance, and receiving of His mercy and grace. He/she receives the greatest of joy in this life and a fullness of joy in the life to come. It’s about time and eternity! I REJOICE in all the Lord has taught me about time and eternity. But, I am still a babe in the woods. This I know, He is the Way, the TRUTH, and the LIGHT, and the life (John 14:6).

David W. Allan

Photo:  CC Wikimedia