• Kogasa@programming.dev
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    27 天前

    That’s not relevant to what they said, which is that distances can’t be imaginary. They’re correct. A metric takes nonnegative real values by definition

    • Brainsploosh@lemmy.world
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      27 天前

      Why can’t a complex number be described in a Banach-Tarsky space?

      In such a case the difference between any two complex numbers would be a distance. And sure, formally a distance would need be a scalar, but for most practical use anyone would understand a vector as a distance with a direction.

      • Kogasa@programming.dev
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        27 天前

        The distance between two complex numbers is the modulus or their difference, a real number