• Knock_Knock_Lemmy_In@lemmy.world
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      6 months ago

      It would only work on earth because we’ve only given the time/space machine information about the rotation of the earth.

      But my question is more about science theory than fiction. Does observing gravity give any information about how fast that mass is rotating?

      • Atomic@sh.itjust.works
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        6 months ago

        “It would only work on earth because we’ve only given the time/space machine information about the rotation of the earth.”

        So you’re the one that only wants it to work on earth then.

        And no. “Observing” Gravity does not give any information of how fast an object is spinning around it’s own axis.

        • Knock_Knock_Lemmy_In@lemmy.world
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          6 months ago

          So you’re the one that only wants it to work on earth then.

          No. Are you suggesting we supply this machine with the rotational velocity of all planets in the known universe? Or some other solution?

          How could we jump to a planet on the other side of the galaxy?

              • Atomic@sh.itjust.works
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                6 months ago

                No, some are talking about how it needs to detect gravitation from other planets.

                That has nothing to do with a time machine working on earth.

                • Knock_Knock_Lemmy_In@lemmy.world
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                  6 months ago

                  The time machine would use gravity so it can arrive at the same relative position in a different time. But that only gets you on the planet, not the same position on the planet.

                  How would rotational movement be accounted for in a generic way?

                  • Atomic@sh.itjust.works
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                    6 months ago

                    How would rotational movement be accounted for in a generic way?

                    I don’t know how it would be accounted for in your imagine time-machine. Because they don’t exist.

                    What I do know. Is that you don’t need gravity to “detect” earths rotational speed. Because we already know what it is.