• Karyoplasma
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    8 months ago

    Backwards time travel is physically impossible. You would need to travel at truly negative speed to achieve it, but the magnitude of speed is always positive.

    • Chrobin
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      8 months ago

      Correction: You’d need to travel with a speed higher than the vacuum speed of light.

      • Karyoplasma
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        8 months ago

        Thinking about it, it’s even more complicated than that. You’re right that a negative speed would not work since the square of a negative number is positive anyway. But a speed higher than c would result in a negative square root, so no real solution. Also, traveling at exactly the speed of light would divide by zero lol

        But maybe our formula is wrong. Or it’s just impossible, who knows?