• 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.

  • nieceandtows@programming.dev
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    1 year ago

    I don’t remember the name of the novel, so somebody help me with this. The concept is basically that scientists invent time travel, but use it as a teleportation device instead. Set the machine by a few seconds, you teleport the distance covered by the Earth during that time. They even use the technique to plan for an assasination of Kim Jong Un. Loved that one. Some innovative sequences using the ‘time machine’.

    Edit: Found it. It’s actually two books (original and sequel).

    Split Second - https://www.goodreads.com/book/show/26216031-split-second

    and

    Time Frame - https://www.goodreads.com/book/show/37946554-time-frame

    The first book takes its time revealing the ‘time travel’, but the second book dives head first into using the technology proficiently.

    • zerodawn@leaf.dance
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      1 year ago

      Accidentally read the second book thinking it was a stand alone. The story still held up so i made it half the book before i realized my mistake

      • nieceandtows@programming.dev
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        1 year ago

        It’s actually marketed as a standalone sequel, so you weren’t too far off. Plus I think the first one was more of an action thriller than about this invention. I actually don’t remember much from the first one. Most of what I remember is from the second one.

  • bleachisback@programming.dev
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    1 year ago

    Same spot relative to what? What object do time machines use as a reference for their coordinates? It would make sense to be Earth, so it would be in the same spot all the time.

    • SkyeStarfall
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      1 year ago

      Weeeeell, not exactly.

      It is true that things are all relative to each other. But think about it this was, if you fly out in a Starship in one direction for a light year, then turn around exactly 180 degrees and fly back, you wouldn’t arrive back at earth, right? Mainly because things are accelerating due to gravity. And acceleration breaks symmetry.

      It would of course depend on how time travel works, but since time and space are linked, it wouldn’t be unreasonable to assume that you follow the same trajectory in space as you move through time. But that would be a straight line in the space+time dimensions still. Think of the paths in Minkowski diagrams.

  • bitcomrade@mander.xyz
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    1 year ago

    In this case, it makes sense to time travel from space and land on a planet upon arrival. Maybe all UFOs are just time travellers after all?🤔

  • SkyNTP@lemmy.ca
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    1 year ago

    Weak premise considering the principles of relativity, and how our current understanding of time travel is basically rooted in SPACE-time.

    • ledtasso@lemmy.world
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      1 year ago

      Yeah, the earth IS in the same place all the time relative to its own frame of reference.

      • stebo02@sopuli.xyz
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        1 year ago

        which makes you wonder what frame of reference would be used when you’re time traveling to decide what location you go to

    • Flying Squid@mander.xyzOP
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      1 year ago

      I read that ages ago. Back in high school, in fact (I’m 46). I don’t remember it except the chapter where time is a flock of birds that you have to try to catch to stay youthful. The children can catch them but always let them go and the adults can never catch them.

        • Flying Squid@mander.xyzOP
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          1 year ago

          I remember it was in the new books section of the school library and I was attracted to it immediately and spent the day reading it instead of paying attention in my classes. I need to read it again. Thanks for bringing it up!

  • MNByChoice@midwest.social
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    1 year ago

    I always assumed that teleportation would need to also be present for time travel. Clearly, just an assumption.

    • gens@programming.dev
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      1 year ago

      If they were orbiting a star for long enough, maybe. (Long enough = thousand or millions of years) Maybe a skeleton in a small cloud ?

      • t_jpeg@lemmy.world
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        1 year ago

        I agree, you have to time travel to travel faster than light no? (my understanding of physics id very elementary)