Uniqueness of asymptotically conical Kähler-Ricci flow
Longteng Chen
TL;DR
This work addresses the uniqueness of the Kahler-Ricci flow starting from a Kahler cone with a smooth canonical model, showing that under a matching conical data, cohomology, Killing-field, and curvature bounds, the forward self-similar flow associated to a given expanding gradient Kahler-Ricci soliton is the unique evolution. The strategy reduces the problem to a complex Monge-Ampère equation by exploiting the soliton symmetry via the Killing field $JX$, and then employs an energy method on the normalized flow to prove a static flow, yielding equality of the two evolutions. The results connect and extend Feldman-Ilmanen-Knopf and Conlon-Deruelle-Sun, providing a partial answer to questions about desingularizations of Kahler cones and the selection principle for AC flows, with implications for uniqueness in non-compact Kahler geometry. The approach combines detailed a priori estimates at spatial infinity, barrier arguments, and a robust interplay between geometric analysis and complex Monge-Ampère techniques, highlighting the role of curvature decay, the obstruction tensor, and soliton potentials in establishing rigidity of AC desingularizations.
Abstract
We study the uniqueness problem for the Kähler-Ricci flow with a conical initial condition. Given a complete gradient expanding Kähler-Ricci soliton on a non compact manifold with quadratic curvature decay, including its derivatives, we establish that any complete solution to the Kahler-Ricci flow emerging from the soliton's tangent cone at infinity--appearing as a Kähler cone--must coincide with the forward self-similar Kähler-Ricci flow associated with the soliton, provided certain conditions hold. Specifically, if its Kähler form remains in the same cohomology class as that of the soliton's self-similar Kähler-Ricci flow, its full Riemann curvature operator is bounded for each fixed positive time, its Ricci curvature is bounded from above by A/t, its scalar curvature is bounded from below by -A/t, and it shares a same Killing vector field with the soliton metric. This paper gives a partial answer to a question in paper of Feldman-Ilmanen-Knopf, and generalizes the earlier work of Conlon-Deruelle and the work of Conlon-Deruelle-Sun.
