• Kethal@lemmy.world
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    1 year ago

    It’s already defined that way - from Wikipedia "From 1983 until 2019, the metre was formally defined as the length of the path travelled by light in a vacuum in 1/299792458 of a second. After the 2019 redefinition of the SI base units, this definition was rephrased to include the definition of a second in terms of the caesium frequency ΔνCs. "

    • Melatonin@lemmy.dbzer0.com
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      1 year ago

      Just because it’s defined as some section of a light year does not mean it’s using a light year as a reference. You could use a foot and find the fraction of a light year that represents it, but that doesn’t mean that the foot is based on a light year.

      I’m saying the short measure that we use on a daily basis might be a BASE 10 portion of a light year. Not 1/299792458 of a light second.

      P.S. It’s like being on Reddit, being download for conjecturing.

      • Kethal@lemmy.world
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        1 year ago

        I see what you mean. That is just as arbitrary as using the Earth’s size or any other reference. There’s nothing special about a year.

          • accidental@lemmy.sdf.org
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            1 year ago

            it’s a hard thing for me to wrap my head around, but it’s cool when you think about it: there’s actually no possible shared reference; even with atomic clocks, based solely on the bouncing of cesium atoms ticking away, the distance travelled is dependent on acceleration in your reference frame.

            relativity really is!