Projective twistor space
= Projective twistor space
{title2=$\mathbb P\mathbb T\cong\mathbb{CP}^3$}
The <projective space> of one-dimensional complex subspaces of <twistor space>. A point corresponds to an <alpha-plane> in <complexified compactified Minkowski space>; a projective line corresponds to a spacetime point.