Tangent Flows of K\"ahler Metric Flows

Max Hallgren; Wangjian Jian

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arXiv · 2202.06185

Tangent Flows of K\"ahler Metric Flows

Max Hallgren·Wangjian Jian

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Abstract

We improve the description of $\mathbb{F}$-limits of noncollapsed Ricci flows in the K\"ahler setting. In particular, the singular strata $\mathcal{S}^k$ of such metric flows satisfy $\mathcal{S}^{2j}=\mathcal{S}^{2j+1}$. We also prove an analogous result for quantitative strata, and show that any tangent flow admits a nontrivial one-parameter action by isometries, which is locally free on the cone link in the static case. The main results are established using parabolic regularizations of conjugate heat kernel potential functions based at almost-selfsimilar points, which may be of independent interest.

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BibTeX RIS

Max Hallgren, Wangjian Jian. 2022-02-13. Tangent Flows of K\"ahler Metric Flows. https://arxiv.org/abs/2202.06185

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