A Ricci-type flow on globally null manifolds and its gradient estimates

Locally, a screen integrable globally null manifold $M$ splits through Riemannian leaf $M'$ of its distribution and curve $\mathcal{C}$ tangent to radical distribution. The carries lot geometric information about and, in fact, forms basis for the study expanding non-expanding horizons black hole theory. In present paper, we introduce degenerate Ricci-type flow via intrinsic Ricci tensor $M$. Several new gradient estimates regarding are proved.