Reposting bc I dun goofed before

  • @[email protected]
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    39 months ago

    How is the shortest measurable amount of time it’s possible to measure with the physics of our universe arbitrary?

    • @Blue_Morpho
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      29 months ago

      It’s arbitrary in the same way measuring the time between photon absorption/emission in a cesium atom is arbitrary or the rotation of our planet is arbitrary.

      Picking the smallest is arbitrary just like picking a larger interval.

      In the cesium clock case, you count 9192631770 because it’s close to 1 second we already are familiar with and arbitrarily say 9192631770 transitions is defined as 1 second.

      For example Planck time is defined as 5.391247(60)×10−44 seconds. But what is that second? It’s the arbitrary 9192631770 cesium transitions we picked because it’s close to the second that come from Earth’s spin.

      • @[email protected]
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        39 months ago

        Planck time doesn’t appear to be arbitrary, but a feature of our universe, hence the shortest measurable unit of time. It’s length in seconds is arbitrary because seconds are arbitrary. And seconds are arbitrary because the only non-arbitrary unit of time we have found so far is too unwieldy to use for anything but scientific purposes, and it’s very unwieldy for many of those.