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  "body": "\n## Summary\n\nElliptic geometry is the [[non-Euclidean geometry|SPCYMFN5V2]] of constant positive curvature.\nIn it, any two points determine exactly one line, and any two lines meet in exactly one point.\nIts standard model is the [[real projective space|1DDYB6VVSR]], seen as the sphere with antipodal points identified.\nThere are no parallel lines, and the angle sum of a triangle exceeds $\\pi$.\nTogether with Euclidean and [[hyperbolic geometry|GN4N94GQ0Z]] it is one of the three classical geometries of constant curvature.\n\n## Explanations\n\n### L1 human\n\nStart with [[spherical geometry|SQ9RQVANMG]] on a globe, where the lines are great circles.\nThere, two great circles always cross twice, at opposite points of the globe.\nNow declare each pair of opposite points to be a single point.\nThen two lines cross exactly once, and two points lie on exactly one line, as in the plane, yet there are still no parallels.\nThe resulting geometry is elliptic geometry; it is finite in size, and no two points are more than a quarter of a great circle apart.\n",
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