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Scientists are hoping to redefine the second – here's why
(theconversation.com)
This is a most excellent place for technology news and articles.
Unfortunately this is a bit like the imperial system where you get multiple units of measurement. There is the standard foot-long, which is twelve inches, and there is the $5 foot-long™, which is only 11 inches
Which is also further befuddled by bragging teenage boy foot long which is around 5"