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The historical significance of urban centers
The impact of cultural and technological advances
The role of urban centers in shaping society
As early as 1955, researchers started to develop atomic clocks, which relied on the laws of physics to establish a new foundation for timekeeping.
An atom consists of negatively charged electrons orbiting a positively charged nucleus at a consistent frequency. You can lightly disturb an electron's orientation if you expose an atom to an electromagnetic field such as light or radio waves.
If you briefly tweak an electron at the right frequency, the vibration will resemble a ticking pendulum and can tick for centuries.
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The second as we know it was one introduced in the late 1500s when the Gregorian calendar began to spread across the globe alongside British colonialism.
The Gregorian calendar defined a day as a single revolution of the Earth about its axis. A day could be divided into 24 hours, each hour ...
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Before timekeeping could go fully atomic, countries had to decide which atom would work best.
At the Thirteenth General Conference of the International Committee for Weights and Measures in 1967, researchers decided on Cesium-133.
The element conformed to the following specifications...
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Determining how many ticks of a caesium atom were in a second, the conference used the most precise astronomical measurement of a second available at the time.
They started with the number of days in a year and divided it down. Compared to the atom’s ticking rate, one second was de...
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The second only became important when society became interconnected through fast-moving railways where cities needed to agree on exact timekeeping.
By the 1950s, several global systems required every second to be accounted for with as much precision as possible.
Today, devices are sy...
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