Correlation (projective geometry)
From Wikipedia, the free encyclopedia
A correlation is a reciprocity (collineation from a projective space onto its dual space, taking points to hyperplanes and preserving incidence) with the identity as the associated automorphism.
If a correlation σ is involutory (that is, two applications of the correlation equals the identity: σ²(P)=P for all points P) then it is called a polarity. If the associated matrix is symmetric, it is called an orthogonal polarity; if the matrix is skew-symmetric, it is called a null polarity or a symplectic polarity.
 |
This geometry-related article is a stub. You can help Wikipedia by expanding it. |
