 Null twistor

A nonzero twistor null for the twistor Hermitian form. Its projective class determines a real null geodesic in compactified Minkowski space. For nonzero $\pi$, its affine real solutions of the twistor incidence relation have the form $x=x_0+r{\overline{\pi }}^A{\pi }^{A^{\prime }}$, $r\in \mathbb{R}$. Twistors with $\pi =0$ encode generators at infinity rather than finite affine solutions.