Redefining The Kilogram: Turning A Piece Of Metal Into A Math Problem

In November, scientists and diplomats voted unanimously to redefine the kilogram. They decided the kilogram will no longer be based on a physical piece of metal, but on a math problem instead.

Here & Now's Jeremy Hobson learns more about what this change means from Patrick Abbott, a physicist at the National Institute of Science and Technology (@usnistgov).