• TheLeadenSea@sh.itjust.works
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    4 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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      4 months ago

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

      • NateNate60@lemmy.world
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        4 months ago

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

        • supernicepojo@lemmy.world
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          4 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

          • SparroHawc@lemmy.zip
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            4 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.

      • Zkuld@lemmy.world
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        4 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.