Share

Weight watchers: How science sets the table for tech advances

Ever wonder how scientists determine the exact weight of a kilogram? Or specify what exactly is an ampere of electricity? Or a mole of a chemical substance? Or agree on the kelvin, a basic measurement of temperature?

You may think these things are somehow constant and unchanging, the way nature intended. Not so. Scientists argued for decades before settling on definitions. But now these basic measurement standards — vital for science, technology and commerce — are set for a major overhaul.

Why? Because scientists now agree on better and more modern ways to measure these weights and forces. In recent weeks, delegates from governments around the globe ratified the changes, propelling the pops of champagne corks worldwide. “This is big,” metrologist Zeina Kubarych told nature.com. “It’s the best thrill ride you can get in metrology” — the study of scientific measurement. (See what you’ve learned in only three paragraphs?)

In this momentous decision, two forces have collided that are often in short supply in science and government: exemplary precision and general agreement.