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arXiv · 2509.05802

A note on a diffeomorphism criterion via long-time Ricci flow

Shaochuang Huang·Zhuo Peng
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Abstract

In this note, we give a diffeomorphism (to $\mathbb{R}^n$) criterion via long-time Ricci flow and show some applications. In particular, we provide an affirmative answer that the conclusion in [Manifolds with small curvature concentration, Ann. PDE, 2024] by Chan, Lee and the first named author and [Removing scalar curvature assumption for Ricci flow smoothing, Bull. Lond. Math. Soc., 2025] by A. Martens about manifolds with small curvature concentration can be improved to diffeomorphism in dimension $4$.

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Shaochuang Huang, Zhuo Peng. 2025-09-06. A note on a diffeomorphism criterion via long-time Ricci flow. https://arxiv.org/abs/2509.05802

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