Markus Wolff: Null mean curvature flow, Part 2: The Return of Ricci flow

We consider null mean curvature flow along the standard lightcone in the de Sitter spacetime. This flow was first studied by Roesch--Scheuer along null hypersurfaces for the detection of MOTS, and independently by the author in the specific case of the standard Minkowski lightcone. Similar to Minkowski case, null mean curvature flow along the de Sitter lightcone can be related to 2d-Ricci flow in the conformally round case by an appropriate rescaling. Building on this rescaling procedure, we analyse singularity formation, and asymptotic behavior of the flow.