A leading American expert on Iran’s alleged nuclear weapons program asserts the U.S. Office of the Director of National Intelligence’s new report applied an obsolete definition when it assessed last ...

For the first time those little numbers that appear beneath some of the commonest elements in the periodic table boxes are about to change from a single value to an interval of numbers An ...

The length of a second hasn't been updated in 70 years. That may change soon. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. The definition of a ...

An exchange of crypto tokens between two different blockchains in a single trade. To accomplish an atomic swap, a crypto wallet and decentralized crypto exchange must support cross-chain swaps. The ...

For decades, atomic clocks have provided the most stable means of timekeeping. They measure time by oscillating in step with the resonant frequency of atoms, a method so accurate that it serves as the ...

This week the kilogram got a new definition – one that rests on a quantity of light. The old kilogram was defined by a platinum cylinder kept in a vault in Paris, and at first glance, that system ...