Digital Transformation at a very fundamental level

Roberto Saracco November 20, 2018 Blog 325 Views

The Kibble balance measures a mass through balancing it with the forces generated by a current flowing in a coil immersed in a magnetic field. It is extremely precise and being based on the Plank constant it does not change in time and space. You could use it on the other side of the universe a billion years from now and be sure you’ll get a precise measurement. Image credit: NIST – https://www.nist.gov/si-redefinition/kilogram-kibble-balance

I don’t know if it escaped your attention but since 1983 it is no longer possible to say that the speed of light is 299,792,458 meter per second. The reason is that since 1983 the meter is defined as the distance travelled by light in vacuum in 1/299,792,458 of a second. And what is a second? Well it is the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.
Since the meter is defined from the light it does not make any sense to say what is the speed of light (that requires using a meter and a clock but now the meter is a consequence of the light movement…, no longer a bar of platinum iridium preserved at Sevres).

Next May, May 2019, also the unit of mass (that placed in a specific location result in the unit of weight in that location), will no longer be a physical object, a block of platinum iridium preserved in Paris (you can ask for a certified copy for 85,000$ by the way), but on a physical constant, the Plank constant.

This new definition of a kg has the advantage of being usable everywhere in the universe and it would have been good 10 billions years ago, it will be good 10 billion years from now. As an added bonus it is also pretty cheap since it is a definition made of bits. You just need to know the Plank constant (better to trust a computer to remember it) and there you are. By applying physical laws you can measure the mass (and hence the weight) of any object. Now, do not expect to see this new definition of kg adopted at your grocery store: a scale based on the Plank constant (see photo) is a quite sophisticated tool and pretty expensive!

When I saw this news I connected it to the ongoing digital transformation, we are moving from objects to bits in a growing number of areas, trusting more the immaterial world than the physical one. In a way it is like going back to Greek philosophers over 2000 years ago that declared truth shall be sought not looking at what we see (since what we perceive can a distortion) but by reasoning. In a way they claimed the need to exploit the “soft” to understand the “hard”. Yes, I know, I might be stretching it a little be.