Comments by "Lawrence D’Oliveiro" (@lawrencedoliveiro9104) on "The kg is dead, long live the kg" video.

  1. 2:12 Apparently it has lost some 50µg of mass since its creation. So yes, there is uncertainty.
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  2. 0:46 Not just any old metal, but a platinum-iridium alloy, as I recall. Also the same material used by Isaac Asimov for his (fictional) “positronic brains”.
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