• xia@lemmy.sdf.orgOP
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      18 hours ago

      Does this mean the concept of infinity requires an infinite number of infinities?

      • Leate_Wonceslace@lemmy.dbzer0.com
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        9 hours ago

        Informally, yes. Formally, no. There is no cardinal sufficient such that every cardinal can fit in a set with that cardinality. Isn’t that fascinating? There’s too many infinities for us to mathematically express how many infinities there are.

  • henfredemars@infosec.pub
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    2 days ago

    Why? What does it mean for something to be real?

    I believe pure mathematics isn’t concerned with its correspondence with reality.

    • xia@lemmy.sdf.orgOP
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      1 day ago

      I recall hearing a quote from the guy that coined the term “imaginary number”, and how he regretted that term because it conveys a conceptualization of fiction. IIRC, he would rather that they would have been called “orthogonal numbers” (in a different plane) and said that they were far more real that people tend to hold in their mind. I think he said “they are as real as negative numbers” along the same lines of one not being able to hold a negative quantity of apples, for example.

      The stray shower thought (beyond simply juxtaposing the discordant terms of ‘imaginary’ and ‘real’) was that infinity by contrast is a much weaker and fantastic concept. It destroys meaningful operations it comes into contact with, and requires invisible and growing workarounds to maintain (e.g. “countably” infinite vs “uncountably” infinite) which smells of fantasy, philosophically speaking.

      • TempermentalAnomaly@lemmy.world
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        7 hours ago

        So Descartes coined the term specifically as a dig because he didn’t see any geometric possibilty to the concept. The concept seems to have roots going back to ancient Egypt, but the modern inquiry goes to the Renaissance. I think Gauss wanted to call them laterals.

      • VoterFrog@lemmy.world
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        15 hours ago

        It destroys meaningful operations it comes into contact with, and requires invisible and growing workarounds to maintain (e.g. “countably” infinite vs “uncountably” infinite) which smells of fantasy, philosophically speaking.

        This isn’t always true. The convergent series comes to mind, where an infinite summation can be resolved to a finite number.

      • xia@lemmy.sdf.orgOP
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        1 day ago

        Furthermore, it is meant to highlight the fact that people gleefully embrace the concept of infinity, but try their hardest to avoid and depreciate the concept of imaginary numbers. It would appear to me that the bias ought to be reversed.

        • xia@lemmy.sdf.orgOP
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          19 hours ago

          A circle has one edge/side, that is grade-school geometry. There is no reason to engender confusion by trying to make it into a polygon or introducing infinity. Your model of shapes does not seem to account for curved edges.

          Consider a stereotypical pizza slice. One might plainly say that it is a “like a triangle but one edge is curved” without falling into a philosophical abyss. :)

          • VoterFrog@lemmy.world
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            15 hours ago

            It’s quite useful, though, to understand a curve or arc as having infinite edges in order to calculate its area. The area of a triangle is easy to calculate. Splitting the arc into two triangles by adding a point in the middle of the arc makes it easy to calculate the area… And so on, splitting the arc into an infinite number of triangles with an infinite number of points along the arc makes the area calculable to an arbitrary precision.

              • VoterFrog@lemmy.world
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                1 hour ago

                The number which famously has an infinite number of digits? I thought we were arguing against the real-ness of infinity.

                Also note: the method I was describing is one of the ways in which pi can be calculated.

  • TranquilTurbulence@lemmy.zip
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    1 day ago

    Imaginary numbers have a specific value, just like all the normal numbers we use on a daily basis. Infinity is not a specific value. Instead, it’s a qualitative property like “flat”, “periodic”, or “symmetric”.

    • QuarterSwede@lemmy.world
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      10 hours ago

      I think of it this way, infinity is an action. It’s not a “thing.” This is why it’s not countable. It doesn’t stop to be counted.

      • TranquilTurbulence@lemmy.zip
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        8 hours ago

        What do you mean by action? Like, how running or writing are actions people can take? So maybe infinity would be an action a group of numbers can take?

  • Orbituary@lemmy.world
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    2 days ago

    Amazing. Your shower thought is incorrect on both counts. Perhaps you meant to say “conceivable?”

    • Windex007@lemmy.world
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      2 days ago

      I’m guessing they maybe mean that they have a more trivial practical resolution to real numbers, in that i^2=-1?

      Kinda like “yeah they’re imaginary but I understand that if I hit them with a certain stick they become real”