That’s the kind of work that goes into defining the meter, the second, and other international standard units of measure ... are elements on the periodic table. Unlike even the top measuring ...

This week, Sam Kean takes a look at some ridiculously precise standards — the meter, the second, and other international standard units — and ... on the periodic table, cesium has one more ...

For these reasons, rulers throughout history—Charlemagne, Alexander the Great, Louis XIV, Moses—all tried, in vain, to impose standard units across their kingdom. (In the Old Testament ...