Stability of asymptotically conical gradient Kähler-Ricci expanders
Longteng Chen
TL;DR
The paper studies the stability of the normalized Kähler-Ricci flow on non-compact manifolds admitting an asymptotically conical gradient expanding Kähler-Ricci soliton. It reduces the flow to a complex Monge-Ampère equation using the Killing field $JX$ and applies a parabolic maximum principle to obtain global existence and uniform estimates on space-time. Under Condition II, the flow exists for all time and converges smoothly to an asymptotically conical gradient Kähler-Ricci expander; if the initial perturbation satisfies a quantitative decay, the limit coincides with the original soliton. The results extend stability phenomena known for Kähler-Einstein and compact cases to AC expanders, highlighting the role of AC geometry and soliton symmetries in governing long-time behavior. This contributes to understanding the moduli of AC solitons and the asymptotic structure of noncompact Kähler-Ricci flows with soliton symmetries.
Abstract
In this work, we consider a perturbation of an asymptotically conical gradient expanding Kähler-Ricci soliton metric $g$ in the same Kähler class. We demonstrate that, under suitable assumptions, the normalized Kähler-Ricci flow starting from the initial perturbed metric exists for all time and converges uniformly to an asymptotically conical gradient expanding Kähler-Ricci soliton metric $g_\infty$. Moreover, if the perturbed initial metric is asymptotic to $g$ at spatial infinity, then the limiting metric coincides with the original soliton, that is, $g_\infty = g$.
