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Constants and units

Constants and units

SI gets a makeover

03 Nov 2018

An upcoming change to SI units – due to be officially approved this month – will mark the end of a long journey from defining quantities in terms of objects to using precise, unchanging and universal constants of nature. Benjamin Skuse tells the story

SI units
(Courtesy: BIPM/iStock/iSerg)
On the outskirts of Paris, eight metres below ground in a climate-controlled vault, sits a 143-year-

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Benjamin Skuse is a freelance science writer based near Bristol, UK, e-mail bskusescicomm@gmail.com
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