• Knusper@feddit.de
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    1 year ago

    Well, I’m glad we got to the bottom of what’s unrealistic about traveling back in time…

    • Calavera@lemm.ee
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      1 year ago

      Time and space are pretty much linked so if you travel in time you can travel in spacetime :)

      • Knusper@feddit.de
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        1 year ago

        Yeah, but to my knowledge, you can only go forwards in time.

        What you can do, is go forwards at a slower speed. So, if you sat yourself in a spaceship and accelerated to e.g. 10% of the speed of light, you might get out after what you perceive as a few years and find yourself in the year 2200 (I did not do the math), but you cannot go back from there.

        Causal chains always have to follow causality. They can just do so less quickly, because, as far as my current understanding goes, the speed of light is actually the speed of causality.

        (Sorry to bonk you with so much physics. I know that initial statement could have also come from someone who’s never heard of the theory of relativity…)

        • AEsheron@lemmy.world
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          1 year ago

          The thing is, a time traveling device would be like the one on Futurama. It just makes time flow at different rates. What people generally think of is a time teleport. And due to the nature of spacetime, a time teleport is indistinguishable from a space teleport. So any teleport should require precise spacetime coordinates, and n9t jist either space or time coordinates.

          • Hikiru@lemmy.world
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            1 year ago

            Another interesting thing about futurama‘s time travel is that instead of going backwards in time, they kept going forward until another Big Bang happened, creating a universe identical to their old one. Then they were able to just keep going forward until they reached when they left

        • fkn@lemmy.world
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          1 year ago

          I think it’s more correct to say that we don’t know how to travel in the other direction on the time axis. It could also simply be our perception of time only works unidirectionally.

          From a mathematics point of view, nothing is preventing going backwards in time… We simply don’t perceive time that way.

          Practically, this does nothing for us.