E: /stoned

  • qantravon@startrek.website
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    2 days ago

    “The length of the path travelled by light in vacuum during a time interval of ⁠1/299792458⁠ of a second, where the second is defined by a hyperfine transition frequency of caesium.”

    This is the actual definition, but it’s also pretty weird.

    • slazer2au@lemmy.world
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      2 days ago

      And here I thought it was that sick of metal in the wall in France when it is 21 degrees C

      • Björn Tantau@swg-empire.de
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        2 days ago

        They redefined it a few years ago to base all units on some objectively measurable natural constant. Because that stick of metal might still decay or warp or something and you don’t always want to travel to France when you want to know the length of a meter. Much easier to measure the atoms and light you have on hand.

        • Natanael@infosec.pub
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          1 day ago

          Updating the kilogram standard took them forever because you need really reliable force measurement instruments and very precise calibration

      • BastingChemina@slrpnk.net
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        1 day ago

        It was defined as

        one ten-millionth of the shortest distance from the North Pole to the equator passing through Paris.

        The stick of metal in Paris is just so people don’t have to do measure the distance between the north pole and the equator each time they want to check their measuring tool.