Everything comes in pairs
March 11, 2025
We saw in the previous tutorial that projective geometry arose out of perspective painting by the addition of new elements, first noticed by Renaissance painters, where parallel lines and planes meet.
The addition of these new elements in projective geometry (PG) had unexpected and far-reaching consequences. To simplify the discussion, we focus now on 2D projective geometry, the projective plane $P(\mathbb{R}^2)$. It arises from the euclidean plane $\mathbf{E}^2$ by adding an ideal line along with all its points, the ideal points of the projective plane.
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