• Nibodhika@lemmy.world
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    9 months ago

    Uhh, relativity, fun. This gets a lot more mind boggling, imagine 3 people, A and B are in a train and C is an observer outside. From C point of view, B will pass him first, then A. This train is going at 50% the speed of light and it’s very long, A and B are 1 second light apart, i.e the distance that light takes 1 second to travel.

    If A shines a flashlight B will see it 1 second later. However from C point of view since the light was shone the train moved forward 0.5 light seconds. So the light has to travel 1.5 light seconds distance, and it does so in exactly 1.5 seconds. So the observers disagree on the distance the light travel, but also disagree on the time it took, but they agree on the speed of light.

    This makes things weird, because both A and B say that 1 second passed, but C says that 1.5 seconds passed. This means that people moving faster experience time slower. Which means that if you take two twins, put one on a fast moving ship, e.g. 80% speed of light, by the time he comes back only a few minutes would have passed for him, but years would pass for the other.

    • MonkderZweite@feddit.ch
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      9 months ago

      There was once an experiment where a particle traveling at 99.999…% the speed of light aged 1 second in 5 minutes. Conclusively, next to lightspeed moves time 300x faster than our speed in universe + gravitation dent.

      Question: is even faster time possible in a huge enough gravitation dent (neutron star)?

      • Nibodhika@lemmy.world
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        9 months ago

        It all depends on the amount of 9s.

        At 99% speed of light you age 8.5 seconds per every minute. At 99.9% it’s 2.7 At 99.99% it’s 0.85 At 99.999% it’s 0.27

        At 99.99944444% it approximates what you described, with 1 second becoming 5 minutes. But you can keep adding 9s, at 99.99999% one second becomes over half an hour, and at 99.99999999999999% it becomes over 2 years.

        So on and so forth, so at 99.999…% like you said it’s essentially 0 seconds vs infinite time.

        You can play around with this calculator to get the numbers https://www.omnicalculator.com/physics/time-dilation