Alex Smith
E Band
1/14/18
Redefining the World’s Measurement System
By Alex Smith
On November 16th of 2018, the dreams of scientists across the world came true; it was agreed that the kilogram would be redefined using the unchanging properties of nature. Previously, the kilogram was defined as the mass of an international standard kept in France, nicknamed “the Grand K.” Even though most of the units in the metric system were already based on constants in nature, it was not always this way. At the beginning of the French Revolution, there were approximately 250,000 different units of measurement in use, which made trade difficult because there was no consensus for how units were defined. During this period a great famine took place, and the people of France grew angry with bakers who cheated customers by reducing the amount of bread per one loaf over time, while keeping the price of one loaf constant. People began crying out for standardized weights and measurements. Once the revolutionary government took over, they made it their goal to create a system of units that were timeless and based on nature. For example, to create the meter, they tried to take one fourth of the circumference of the earth, and divided that by 1/10,000,000. To create the kilogram, they took 1/10 of the meter, cubed it, and filled it with water, took the mass of that water, and then created a metal cylinder with that same mass. This mass (the Grand K), was then precisely reproduced and distributed around the world, but the original was safeguarded in France. Until its new redefinition, the definition of the kilogram had been working well around the world. Unfortunately, after having been steamed and showered to be cleansed from contaminants, scientists measured the weight of the original platinum-iridium cylinder against its sister copies and found that it had ever-so-slightly lost mass. This discovery was quite troubling, as it meant that the world’s understand of the kilogram was now wrong, because the Grand K is always right (the definition can never be wrong). Eventually, almost all of the units in the metric system were based on physical constants. The meter was defined as of the distance travelled by light in a vacuum over 1/299,792,458 seconds. The second was defined as “how much radiation corresponds to the transition between two hyperfine levels of the ground state of the Cesium-133 atom.” The kilogram, along with a few other units, were the only units without a natural and timeless definition. So, on the aforementioned date (11/16/18) scientists around the world voted unanimously in the 26th General Conference on Weights and Measures in Versailles to redefine the kilogram (along with other SI units that were previously not based on physical invariants). They decided to use Planck’s constant (a physical constant that relates the energy carried to a photon by its frequency), a fundamental factor in physics, to redefine the kilogram. This vote was a pivotal event in modern science and humanity because it ensured that the kilogram, a crucial unit in our everyday lives, will never change. It also means that anybody with the proper tools can determine the value of a kilogram. However momentous this vote was, the actual change in the definition of the kilogram is not scheduled to occur until the 20th of May this year. Nonetheless, when the change does come into fruition it will have a number of impacts. Because units provide assurance in stability in manufacturing, we may see an increase in production/commerce around the world given that companies will have a newfound confidence in the kilogram. Perhaps even the United States may reconsider their stubborness and join the rest of the world in using the metric system. As far as day-to-day life goes, the redefinition will not have a large impact on us (or our bathroom scales). But, a change Packer students may notice, however, is new scientific instrumentation in the science department calibrated according to the kilogram’s new definition. Even though the redefinition of the SI units may not directly affect everyday life, at least we can rest assured that on May 20th of 2019, we will no longer have to fear the involuntary change of value of our units.
Works Cited
Materese, R. (2018, December 06). A Turning Point for Humanity: Redefining the World's Measurement System. Retrieved January 8, 2019, from https://www.nist.gov/si-redefinition/turning-point-humanity-redefining-worlds-measurement-system
Nasser, L. (2014, July 9). The Meter: The Measure of a Man | Radiolab. Retrieved December 30, 2018, from https://www.wnycstudios.org/story/meter-measure-man
Wei-Haas, M. (2018, November 16). The kilogram is forever changed. Here's why that matters. Retrieved December 30, 2018, from https://www.nationalgeographic.com/science/2018/11/kilogram-forever-changed-why-mass-matters/
≤ kg | Radiolab. (2014, June 13). Retrieved December 30, 2018, from https://www.wnycstudios.org/story/kg
E Band
1/14/18
Redefining the World’s Measurement System
By Alex Smith
On November 16th of 2018, the dreams of scientists across the world came true; it was agreed that the kilogram would be redefined using the unchanging properties of nature. Previously, the kilogram was defined as the mass of an international standard kept in France, nicknamed “the Grand K.” Even though most of the units in the metric system were already based on constants in nature, it was not always this way. At the beginning of the French Revolution, there were approximately 250,000 different units of measurement in use, which made trade difficult because there was no consensus for how units were defined. During this period a great famine took place, and the people of France grew angry with bakers who cheated customers by reducing the amount of bread per one loaf over time, while keeping the price of one loaf constant. People began crying out for standardized weights and measurements. Once the revolutionary government took over, they made it their goal to create a system of units that were timeless and based on nature. For example, to create the meter, they tried to take one fourth of the circumference of the earth, and divided that by 1/10,000,000. To create the kilogram, they took 1/10 of the meter, cubed it, and filled it with water, took the mass of that water, and then created a metal cylinder with that same mass. This mass (the Grand K), was then precisely reproduced and distributed around the world, but the original was safeguarded in France. Until its new redefinition, the definition of the kilogram had been working well around the world. Unfortunately, after having been steamed and showered to be cleansed from contaminants, scientists measured the weight of the original platinum-iridium cylinder against its sister copies and found that it had ever-so-slightly lost mass. This discovery was quite troubling, as it meant that the world’s understand of the kilogram was now wrong, because the Grand K is always right (the definition can never be wrong). Eventually, almost all of the units in the metric system were based on physical constants. The meter was defined as of the distance travelled by light in a vacuum over 1/299,792,458 seconds. The second was defined as “how much radiation corresponds to the transition between two hyperfine levels of the ground state of the Cesium-133 atom.” The kilogram, along with a few other units, were the only units without a natural and timeless definition. So, on the aforementioned date (11/16/18) scientists around the world voted unanimously in the 26th General Conference on Weights and Measures in Versailles to redefine the kilogram (along with other SI units that were previously not based on physical invariants). They decided to use Planck’s constant (a physical constant that relates the energy carried to a photon by its frequency), a fundamental factor in physics, to redefine the kilogram. This vote was a pivotal event in modern science and humanity because it ensured that the kilogram, a crucial unit in our everyday lives, will never change. It also means that anybody with the proper tools can determine the value of a kilogram. However momentous this vote was, the actual change in the definition of the kilogram is not scheduled to occur until the 20th of May this year. Nonetheless, when the change does come into fruition it will have a number of impacts. Because units provide assurance in stability in manufacturing, we may see an increase in production/commerce around the world given that companies will have a newfound confidence in the kilogram. Perhaps even the United States may reconsider their stubborness and join the rest of the world in using the metric system. As far as day-to-day life goes, the redefinition will not have a large impact on us (or our bathroom scales). But, a change Packer students may notice, however, is new scientific instrumentation in the science department calibrated according to the kilogram’s new definition. Even though the redefinition of the SI units may not directly affect everyday life, at least we can rest assured that on May 20th of 2019, we will no longer have to fear the involuntary change of value of our units.
Works Cited
Materese, R. (2018, December 06). A Turning Point for Humanity: Redefining the World's Measurement System. Retrieved January 8, 2019, from https://www.nist.gov/si-redefinition/turning-point-humanity-redefining-worlds-measurement-system
Nasser, L. (2014, July 9). The Meter: The Measure of a Man | Radiolab. Retrieved December 30, 2018, from https://www.wnycstudios.org/story/meter-measure-man
Wei-Haas, M. (2018, November 16). The kilogram is forever changed. Here's why that matters. Retrieved December 30, 2018, from https://www.nationalgeographic.com/science/2018/11/kilogram-forever-changed-why-mass-matters/
≤ kg | Radiolab. (2014, June 13). Retrieved December 30, 2018, from https://www.wnycstudios.org/story/kg
