Thinking of time
28/07/22 01:38
In the 1840’s in New England, the growth of railroads held the possibility of expanding business and industry, but there was a problem that was getting worse. The problem was train accidents. the crashes killed people and the public was growing angry. People accused the railroad companies of cutting corners to increase profits. The problem, however, wasn’t money. It was time. Train conductors set their clocks by the time at their main departure station, found locally by marking the passage of the sun or observing stars. That meant that trains originating in different times were observing different times. With most lines having just a single track on which trains traveled both directions, the practice was for trains to pull onto designated sidings at designated times to allow a train traveling the opposite direction to pass. However, the two trains were traveling to two different times. And there were a lot of times: Boston time, Worcester time, Springfield time.
With the industrial revolution enabling more precise manufacturing, clockmakers were honing their skills. Watches and clocks were becoming more and more accurate. But the pocket watches carried by train conductors were of little use when they did not know the time being reported on the watch of the conductor of a different train. The result was an increase in accidents, causing death, injury and loss of property.
The solution came through a unique collaboration of Harvard College Observatory and Boston clockmaker, William Cranch Bond. Starting in 1849 and continuing for the next 43 years, a time signal originating in the Harvard College Observatory allowed for the synchronization of watches on trains. The result was America’s first time zone. Not only did the Observatory’s time signal allow trains to run on time and avoid accidents, factories were enabled to employ workforces on the same hours, and bankers could time-stamp financial transactions.
The historian Lewis Mumford noted that it was the clock, not the steam engine, that was the most important machine of the industrial revolution. Steam engines may have powered factories and transportation, but it took accurate clocks and a system of synchronizing them for people and their activities to be coordinated enough for efficiency.
The concept of standardized time did not originate with the Harvard College Observatory. Years before, the Royal Greenwich Observatory in London, England, began to proclaim “true” time. In 1833, timekeepers added a ball to a mast at the Royal Greenwich Observatory. The ball would drop precisely at 13:00 (1 pm) each day allowing merchants, factories and banks to adjust their clocks.
In the 1880s a cable was laid under the ocean that connected the Royal Greenwich Observatory with the Harvard College Observatory, establishing the first international time standard. At the International Meridian Conference in Washington DC, more than 25 countries decided that GMT would become the international time standard.
Systems of delivering accurate time involved swinging pendulums, later electronic oscillations of a quartz crystal, and yet later measuring the energy levels of an atom when electromagnetic radiation is applied. Once atomic clocks were developed it was discovered that the clocks were more accurate than the Earth’s rotation. The rotation speed of the earth is slowing down due to gravitational effects from the moon, sun and planets. It is also affected by geological shifts within the core and mantle of the planet, and also by oceanic and climatic changes.
The result is that there is no absolute that is “true” time. Time is a human invention. The most accurate of clocks need to have leap seconds added every so often in order to keep from having time depart from night and day.
Today’s most accurate clocks have deviated from the rotation of the planet as the standard for measuring time. Instead of a second being 1/86,400 of a solar day, it now is based on “a fixed numerical value of the unperturbed cesium ground-state hyperfine transition.” Basically if you bathe cesium in microwaves, they release electromagnetic radiation with a specific frequency. Measure this frequency and you measure the passage of time.
Scientists have gone beyond counting seconds to counting nanoseconds as a standard. This allows for the measurement of very fast objects. And it allows the creation of systems that use objects that are very distant from one another to make accurate measurements. Those measurements are used for the basis of many modern conveniences, including GPS navigation systems. It is no longer just trains and banks, but our entire telecommunications system is based on accurate clocks.
Now laboratories are experimenting with optical technology that may produce a new definition of the meaning of a second within a decade or so. Only time will tell, and it takes time for testing.
Way back, when the first time zones were created, there were those who objected. How could it possibly be the same time in two different places, they asked. The sundial in one place will always read differently than the sundial in another place. They spoke of a basic truth that we often forget. There is no clock on Earth that can ever be perfectly stable or run at exactly the right rate. We have decided to come to agreement despite differences, no matter how small, in how time is measured. We share enough information for trains and planes and satellites to be tracked and measured. We share enough information for our telecommunications systems to work.
The bottom line, however, is that nobody really knows what time it is. That is the true answer to the question posed by the song. No, nobody really knows what time it is.
We have devised a system that works most of the time for most people. And we continue to revise that system, gaining in accuracy. A nanosecond may not mean much to the average person, but when it comes to interplanetary travel, a nanosecond can translate into light years of distance.
Although I don’t really know what time it is - here or on distant planets - I’m pretty sure that the berries are ripe in the garden and when daylight comes it will be time to pick a few more for breakfast. I’ll leave the fine definition of nanoseconds to others - for now at least.
With the industrial revolution enabling more precise manufacturing, clockmakers were honing their skills. Watches and clocks were becoming more and more accurate. But the pocket watches carried by train conductors were of little use when they did not know the time being reported on the watch of the conductor of a different train. The result was an increase in accidents, causing death, injury and loss of property.
The solution came through a unique collaboration of Harvard College Observatory and Boston clockmaker, William Cranch Bond. Starting in 1849 and continuing for the next 43 years, a time signal originating in the Harvard College Observatory allowed for the synchronization of watches on trains. The result was America’s first time zone. Not only did the Observatory’s time signal allow trains to run on time and avoid accidents, factories were enabled to employ workforces on the same hours, and bankers could time-stamp financial transactions.
The historian Lewis Mumford noted that it was the clock, not the steam engine, that was the most important machine of the industrial revolution. Steam engines may have powered factories and transportation, but it took accurate clocks and a system of synchronizing them for people and their activities to be coordinated enough for efficiency.
The concept of standardized time did not originate with the Harvard College Observatory. Years before, the Royal Greenwich Observatory in London, England, began to proclaim “true” time. In 1833, timekeepers added a ball to a mast at the Royal Greenwich Observatory. The ball would drop precisely at 13:00 (1 pm) each day allowing merchants, factories and banks to adjust their clocks.
In the 1880s a cable was laid under the ocean that connected the Royal Greenwich Observatory with the Harvard College Observatory, establishing the first international time standard. At the International Meridian Conference in Washington DC, more than 25 countries decided that GMT would become the international time standard.
Systems of delivering accurate time involved swinging pendulums, later electronic oscillations of a quartz crystal, and yet later measuring the energy levels of an atom when electromagnetic radiation is applied. Once atomic clocks were developed it was discovered that the clocks were more accurate than the Earth’s rotation. The rotation speed of the earth is slowing down due to gravitational effects from the moon, sun and planets. It is also affected by geological shifts within the core and mantle of the planet, and also by oceanic and climatic changes.
The result is that there is no absolute that is “true” time. Time is a human invention. The most accurate of clocks need to have leap seconds added every so often in order to keep from having time depart from night and day.
Today’s most accurate clocks have deviated from the rotation of the planet as the standard for measuring time. Instead of a second being 1/86,400 of a solar day, it now is based on “a fixed numerical value of the unperturbed cesium ground-state hyperfine transition.” Basically if you bathe cesium in microwaves, they release electromagnetic radiation with a specific frequency. Measure this frequency and you measure the passage of time.
Scientists have gone beyond counting seconds to counting nanoseconds as a standard. This allows for the measurement of very fast objects. And it allows the creation of systems that use objects that are very distant from one another to make accurate measurements. Those measurements are used for the basis of many modern conveniences, including GPS navigation systems. It is no longer just trains and banks, but our entire telecommunications system is based on accurate clocks.
Now laboratories are experimenting with optical technology that may produce a new definition of the meaning of a second within a decade or so. Only time will tell, and it takes time for testing.
Way back, when the first time zones were created, there were those who objected. How could it possibly be the same time in two different places, they asked. The sundial in one place will always read differently than the sundial in another place. They spoke of a basic truth that we often forget. There is no clock on Earth that can ever be perfectly stable or run at exactly the right rate. We have decided to come to agreement despite differences, no matter how small, in how time is measured. We share enough information for trains and planes and satellites to be tracked and measured. We share enough information for our telecommunications systems to work.
The bottom line, however, is that nobody really knows what time it is. That is the true answer to the question posed by the song. No, nobody really knows what time it is.
We have devised a system that works most of the time for most people. And we continue to revise that system, gaining in accuracy. A nanosecond may not mean much to the average person, but when it comes to interplanetary travel, a nanosecond can translate into light years of distance.
Although I don’t really know what time it is - here or on distant planets - I’m pretty sure that the berries are ripe in the garden and when daylight comes it will be time to pick a few more for breakfast. I’ll leave the fine definition of nanoseconds to others - for now at least.
