Let’s imagine a world where time machines are invented.

Hypothetically, what’s stopping anyone from travelling to the past, where the dollar is much more valuable, and buying things at a much lower price? What if you then go back to the present, sell those things at a higher price and repeat the cycle? And wtf would happen if everyone there started doing that?

  • Buffalox@lemmy.world
    2·
    5 hours ago

    All speculation on time travel end out in either paradoxes or infinities.
    You are basically wasting your time, time travel is an impossible fantasy and not reality.
    Time can be slowed, but there is no way it’s possible to travel back in time, because the past no longer exist. So there is nowhere to travel to.
    In the same way the future does not exist yet, so you can’t “travel” to that either.
    Time can however be somewhat suspended locally, so if you are suspended in time locally, it will appear as if you are traveling to the future. But in reality you are merely progressing in time faster at a slower pace locally.

      • Buffalox@lemmy.world
        5·
        4 hours ago

        Maybe not because you can’t prove a negative, but since there is no proof that it exist, there is no rational reason to believe it does.
        It’s all wishful thinking and speculation for hundreds of years with nothing to show for it.

        I do however have the proof of logic, because if they do exist, all sorts of logical inconsistencies arise. Which is why fantasies about it, always end out in either infinities or paradoxes.

        I can’t prove an invisible pink unicorn isn’t in my room either. But I can say I can’t see hear or otherwise detect it’s presence, even after thorough investigation, and closing the room off for an extended period of time. I still can’t prove it, but the logical conclusion is the complete an utter lack and absence of an invisible pink unicorn in my room.

        • WoodScientist@lemmy.world
          11·
          3 hours ago

          And yet, you’ve concocted this fantasy that you call “the present,” as if such a thing could exist in a relativistic universe…

          • Buffalox@lemmy.world
            1·
            2 hours ago

            That’s not a concoction or a fantasy, but the actual reality. Or are you trying to argue the present doesn’t exist?

            Time is seemingly an emergent property of causality. But the exact nature of what time is exactly, is not well understood.
            Basic principles about whether time is linear or quantized isn’t even entirely clear.
            But to argue the present doesn’t exist is like arguing nothing really exists, and then I don’t really have anything to say to you, because that’s like solipsism and that’s absolute nonsense not worth debating.

            • WoodScientist@lemmy.world
              1·
              2 hours ago

              https://en.wikipedia.org/wiki/Relativity_of_simultaneity

              The present does not exist. From the previous link:

              It can be argued that special relativity eliminates the concept of absolute simultaneity and a universal present: according to the relativity of simultaneity, observers in different frames of reference can have different measurements of whether a given pair of events happened at the same time or at different times, with there being no physical basis for preferring one frame’s judgments over those of another. However, there are events that may be non-simultaneous in all frames of reference: when one event is within the light cone of another—its causal past or causal future—then observers in all frames of reference show that one event preceded the other. The causal past and causal future are consistent within all frames of reference, but any other time is “elsewhere”, and within it there is no present, past, or future. There is no physical basis for a set of events that represents the present.

              Many philosophers have argued that relativity implies eternalism.[6] Philosopher of science Dean Rickles says that, "the consensus among philosophers seems to be that special and general relativity are incompatible with presentism.

              If two observers will disagree on which events happened in “the present,” then “the present” cannot exist as a real universal entity. “The present” only makes any physical sense in classical, pre-20th century Newtonian mechanics.

              This is why the block universe or eternalism makes more sense.

              • Buffalox@lemmy.world
                1·
                2 hours ago

                It can be argued that special relativity eliminates the concept of absolute simultaneity

                That’s not the same thing. Obviously all experiences are delayed, and therefore about the past, even if it is merely picoseconds.
                In that way we can only experience the past, that is obvious, and not relevant to the existence of an objective present.

                Although we can only experience the present with some delay depending on circumstances, (can be billions of years astronomically) there is zero doubt that there is an objective “present” we all experience and act according to.

                • WoodScientist@lemmy.world
                  1·
                  2 hours ago

                  You’re still imagining that there is some fixed universe playing out at constant time, and that we all just experience the echoes of this present in different orders. This isn’t what relativity says. Clocks traveling near the speed of light don’t just appear to slow down, they actually slow down.

                  Different regions of the universe don’t even experience the same flow rate of time. Someone living on a mountaintop experiences time faster than someone at sea level. And yet you cling to this fantasy of their being some universal “present.” You cannot have a universal present in a universe composed of different flow rates of time!

                  • Buffalox@lemmy.world
                    1·
                    2 hours ago

                    Clocks traveling near the speed of light don’t just appear to slow down, they actually slow down.

                    Which is EXACTLY the ONLY thing I said you can actually do.
                    You can slow down time locally. And for a photon it’s slowed down to a standstill.

                    That does not contradict ANYTHING I’ve claimed.