• raspberriesareyummy@lemmy.world
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    1 year ago

    While this Riemann sphere seems like a useful concept, -∞ = ∞ is an observation that doesn’t seem to hold true outside this spherical model of complex numbers. Just add ∞ to the both sides, and you end up with 0 = ∞ + ∞ which is most certainly not true.

    • Kühe sind toll@feddit.de
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      1 year ago

      0 = ∞ + ∞ which is most certainly not true.

      This is only true if both infinite are the same, but one is negative. As a general statement you’re right, that this is not true.

      • raspberriesareyummy@lemmy.world
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        1 year ago

        Well - in the post I replied to there was explicit talk about +∞ and -∞, upon which I believe it is fair to say that ∞ is positive in this example.

    • blind3rdeye@lemm.ee
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      1 year ago

      Sure. And it also doesn’t help to avoid the problems with division by zero. But lucky we’re posting in the shitpost section, so we don’t have to worry too much about details.

    • MBM@lemmings.world
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      1 year ago

      Just add ∞ to the both sides

      That’s why ∞ - ∞ is left undefined (same as 0/0 and ∞/∞)

      • raspberriesareyummy@lemmy.world
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        1 year ago

        adding ∞ to both sides does not create a ∞ - ∞ situation, though. The substraction is a whole different topic, because it becomes an elimination problem, whereas ∞ + ∞ = ∞