• PeriodicallyPedantic@lemmy.ca
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    3 months ago

    I’m not a math major, but I always considered it that a square is a special case of rectangle, a rectangle is a special case of parallelogram, and a parallelogram a special case of a quadrilateral, a quadrilateral a special case of a simple polygon.

    This shape isn’t a polygon, so it cannot be a square.

    • hansolo@lemmy.today
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      3 months ago

      …and a square has four interior 90 degree angles.

      …and based on the infinite number of sides for a curved line aspect, the “90 degree” angles would all be +/- the limit as it approaches zero, so never truly 90 degrees but always an infinite fraction away.

      • Caveman@lemmy.world
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        3 months ago

        Yeah, we gonna need more rigor on this one.

        “A square is a shape made up of four equally long lines a, b, c, d where a is perpendicular to c and d and parallel to b. Each of these lines meet exactly two other lines at it’s ends.”

        I’m not a mathematician so there might an odd case somewhere in there. Maybe it has to be confined to a shared plane?

        • Sneezycat@sopuli.xyz
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          3 months ago

          Lines are infinitely long… do you mean line segments?

          Wikipedia has a good enough definition: “It has four straight sides of equal length and four equal angles.” Nice and simple.

        • hansolo@lemmy.today
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          3 months ago

          So you’re saying this is the outline of a square in the astral plane? Because it sounds like you’re saying this is a square in the astral plane.

    • PeriodicallyPedantic@lemmy.ca
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      3 months ago

      Hey, that’s my job!

      Also I don’t think that’s technically the technical classification. I think that sidedness is an attribute that simply doesnt apply to curves.
      You can approximate curves with some number of sides, and the approximation gets more accurate as the number approaches infinity, but it doesn’t actually have the infinite sides.

      • YiddishMcSquidish@lemmy.today
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        3 months ago

        If it is a projection, then there are more than two curved sides, which also begs credence to the interpretability of the angles they intersect.

        • danhab99@programming.dev
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          3 months ago

          Well angles between 3 points are always going to be angles. If your choose a different configuration of dimensional parameters you can effectively project a square from the 2D plane into this exact shape, then logically the angles would follow.

    • tetris11@feddit.uk
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      3 months ago

      uhhh, wait. Under what projection is OP’s “square” reduced to an actual square

        • tetris11@feddit.uk
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          3 months ago

          Im gonna need more than that as an explanation. Sandwiches too if you’re making some

          • Machinist@lemmy.world
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            2 months ago

            Imagine you have a cookie cutter in that shape. Cut a cookie as thick as the chord of the largest arc.

            View the new vertical surface of the longest arc that is now a cylindrical section.

            Viola, square. 😁

  • TheLeadenSea@sh.itjust.works
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    3 months ago

    Straight lines. Also two sets of parallel lines. This is one definition of a square, but not the common one.

    • mcqtom@lemmy.world
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      3 months ago

      I believe these lines are straight with a black hole at the centre.

      • Zkuld@lemmy.world
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        3 months ago

        I would guess on a sphere these can be straight yes: The pole goes into the center of cicular thing and radius of the sphere needs to put the other arc on one latitude.

      • NateNate60@lemmy.world
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        3 months ago

        Euclid’s first postulate: Give two points, there exists exactly one straight line that includes both of them.

          • SparroHawc@lemmy.zip
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            3 months ago

            No, it’s still accurate - the straight line goes through the center of the Earth. Only in coordinate systems where ‘straight’ is defined as following the curvature of a surface are there infinite lines between the North and South Poles… and that would be non-Euclidean geometry.

        • supernicepojo@lemmy.world
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          3 months ago

          This only applies in 2nd order real space. Euclidean geometry aside, I agree with at least one line could exist between two points

    • FUsername@feddit.org
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      2 months ago

      Here you can see how things go haywire when skipping minor parts of definitions.

    • jenesaisquoi@feddit.org
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      3 months ago

      Peperoni are bell peppers. I have no idea why the USA chose to use this word to mean salami, instead of, you know, salami.

      • 0ops@lemm.ee
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        3 months ago

        Pepperoni and salami are totally different dude, you might as well be saying that Americans should just call their potatoes “yams”. And you can get both of those sausages and many, many more on your pizza, often at the same time

  • halcyoncmdr@lemmy.world
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    3 months ago

    Someone never had to deal with mathematical proofs, only layman’s definitions.

    All properties of a parallelogram apply:

    • Opposite sides are parallel
    • Opposite sides are congruent
    • Opposite angles are congruent
    • Consecutive angles are supplementary
    • Diagonals bisect each other

    AND

    • All angles are congruent
    • All sides are congruent
    • Diagonals are congruent
    • Diagonals are perpendicular
    • Diagonals bisect opposite angles
    • Eatspancakes84@lemmy.world
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      3 months ago

      Of course, but such strict definitions only come about because smart people come up with examples like OP when you don’t add the full definition.

  • Saarth@lemmy.world
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    3 months ago

    Don’t the internal angles need to be 90°? Two of those right angles aren’t right angles on the inside.

  • burgersc12@mander.xyz
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    3 months ago

    Does no one understand this is a joke, talking about parallel lines and mathematical proofs is pointless when its a fucking meme

    • dontbelievethis@sh.itjust.works
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      3 months ago

      It’s not pointless because you can laugh about a joke and then learn something about math.

      They don’t cancel each other out. They can be at the same place and still work on their own.

    • CyberEgg@discuss.tchncs.de
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      3 months ago

      We do understand it’s a meme and a joke. Just not a very good one, because one can easily poke holes into it.

      • daddycool@lemmy.world
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        3 months ago

        Just not a very good one, because one can easily poke holes into it.

        That’s not how jokes work.

          • daddycool@lemmy.world
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            3 months ago

            No, it depends on if you have humor. Yes, humor is individual, I know. But people without tend to over analyze and try to pick the joke apart, often missing the point.

            A joke doesn’t have to pass every technicality. You thinking it’s bad if it doesn’t, only applies to your humor (or lack there of).

            • CyberEgg@discuss.tchncs.de
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              3 months ago

              Ooh, watch out, the humor police is here! Everything the deem funny is humor and if you don’t find funny what they do you don’t even have humor! Wee-ooo wee-ooo!

        • CyberEgg@discuss.tchncs.de
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          3 months ago

          It’s not about taking it seriously. The meme wants to be a technically correct-meme, where a thing fulfills another things definition and thereby could be deemed the other thing - which creates the absurdity the meme lives off of. But in order for that kind of humour, there cannot be obvious holes in the logic of the joke and these obvious holes are very present in this meme.

          • MBM@lemmings.world
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            3 months ago

            Any maths joke of this type will have obvious holes in it, that’s just how maths works