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Comment by rrr_oh_man

8 hours ago

> math get's really counterintuitive to grasp

People always say that about speed of light stuff, but I don’t get it. Do you have any more examples of counterintuitive math?

Because what you’re describing is basically the equivalent to compound interest in finance. (e.g. investing $100 at 10% interest over 10 years results in $260)

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rrr_oh_man

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MathMonkeyMan  7 hours ago

The proper time (that is, the time the traveler measures on a clock) goes to zero very quickly towards the end. Even with both axes plotted logarithmically, it's just a sudden drop at the end towards light speed.

- [pic](https://home.davidgoffredo.com/hackernews/proper-time-one-li...)

- [plot](https://home.davidgoffredo.com/hackernews/proper-time-one-li...)

jeanlucas  8 hours ago

One million seconds is 11 days, a billion seconds is 31 years.

  • rrr_oh_man  7 hours ago

    Thanks! But same here imho:

                  1,000 seconds =          ~0.01 days (~17 min)
          1,000,000 seconds =         ~11.57 days (~12 days) 
      1,000,000,000 seconds =     ~11,574.07 days (~32 years)
  1,000,000,000,000 seconds = ~11,574,074.07 days (~32k years)

    It all seems quite logical once you put everything into the same unit, I think.

    Maybe it's just our human calendar/time unit rollercoaster (60*60*24*30*12) that's playing tricks on us here.

    • jeanlucas  7 hours ago

      Of course it is logical, we are not discussing the math.

      But it isn't intuitive, you're not used to numbers that big or that grow that fast.

      Few things go from a million to a billion, especially when related to time.

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