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Related papers: Perelman's entropy on ancient Ricci flows

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In this paper, we first introduce the weighted forward reduced volume of Ricci flow. The weighted forward reduced volume, which related to expanders of Ricci flow, is well-defined on noncompact manifolds and monotone non-increasing under…

Differential Geometry · Mathematics 2011-03-21 Liang Cheng , Anqiang Zhu

We prove a uniform Sobolev inequality for Ricci flow, which is independent of the number of surgeries. As an application, under less assumptions, a non-collapsing result stronger than Perelman's $\kappa$ non-collapsing with surgery is…

Differential Geometry · Mathematics 2007-12-11 Qi S. Zhang

We study blow-ups around fixed points at Type I singularities of the Ricci flow on closed manifolds using Perelman's W-functional. First, we give an alternative proof of the result obtained by Naber and Enders-M\"{u}ller-Topping that…

Differential Geometry · Mathematics 2015-10-14 Carlo Mantegazza , Reto Müller

We show that any manifold admitting a non-collapsed, ancient Ricci flow must have finite fundamental group. This generalizes what was known for $\kappa$-solutions in dimensions 2, 3. We furthermore show that this fundamental group must be a…

Differential Geometry · Mathematics 2021-10-07 Richard H. Bamler

We prove long-time existence of the Ricci flow starting from complete manifolds with bounded curvature and scale-invariant integral curvature sufficiently pinched with respect to the inverse of its Sobolev constant. Moreover, if the…

Differential Geometry · Mathematics 2024-03-06 Albert Chau , Adam Martens

We prove that if the Ricci curvature is uniformly bounded under the Ricci-Harmonic flow for all times $t$ \in[0, T), then the curvature tensor has to be uniformly bounded as well.

Differential Geometry · Mathematics 2011-01-07 Anqiang Zhu , Liang Cheng

We use a first-order energy quantity to prove a strengthened statement of uniqueness for the Ricci flow. One consequence of this statement is that if a complete solution on a noncompact manifold has uniformly bounded Ricci curvature, then…

Differential Geometry · Mathematics 2015-07-30 Brett Kotschwar

In this note we determine the first two derivatives of the classical Boltzmann-Shannon entropy of the conjugate heat equation on general evolving manifolds. Based on the second derivative of the Boltzmann-Shannon entropy, we construct…

Differential Geometry · Mathematics 2014-08-21 Hongxin Guo , Robert Philipowski , Anton Thalmaier

Let ${\bf M}$ be a compact Riemannian manifold and the metrics $g=g(t)$ evolve by the Ricci flow. We prove the following result. The Sobolev imbedding by Aubin or Hebey, perturbed by a scalar curvature term and modulo sharpness of…

Differential Geometry · Mathematics 2007-08-29 Qi S. Zhang

We derive a logarithmic Sobolev inequality along the Ricci flow without any restriction on time, which depends only on the initial metric via rudimentary geometric data, assuming only that a certain first eigenvalue is positive. As a…

Differential Geometry · Mathematics 2007-08-29 Rugang Ye

We show uniqueness of Ricci flows starting at a surface of uniformly negative curvature, with the assumption that the flows become complete instantaneously. Together with the more general existence result proved in [10], this settles the…

Analysis of PDEs · Mathematics 2011-08-22 Gregor Giesen , Peter M. Topping

We consider Ricci flow invariant cones C in the space of curvature operators lying between nonnegative Ricci curvature and nonnegative curvature operator. Assuming some mild control on the scalar curvature of the Ricci flow, we show that if…

Differential Geometry · Mathematics 2011-11-04 Thomas Richard

In this expository note, we study the second variation of Perelman's entropy on the space of Kahler metrics at a K\"ahler-Ricci soliton. We prove that the entropy is stable in the sense of variations. In particular, Perelman's entropy is…

Differential Geometry · Mathematics 2018-07-26 Gang Tian , Xiaohua Zhu

We show that any ancient solution to the Ricci flow which satisfies a suitable curvature pinching condition must have constant sectional curvature.

Differential Geometry · Mathematics 2019-12-19 S. Brendle , G. Huisken , C. Sinestrari

For any complete noncompact K$\ddot{a}$hler manifold with nonnegative and bounded holomorphic bisectional curvature,we provide the necessary and sufficient condition for non-ancient solution to the Ricci flow in this paper.

Differential Geometry · Mathematics 2015-06-26 Qihua Ruan , Zhihua Chen

In this paper we consider the Ricci curvature of a Ricci soliton. In particular, we have showed that a complete gradient Ricci soliton with non-negative Ricci curvature possessing a non-constant convex potential function having finite…

Differential Geometry · Mathematics 2020-04-03 Chandan Kumar Mondal , Absos Ali Shaikh

B Wilking has recently shown that one can associate a Ricci flow invariant cone of curvature operators $C(S)$, which are nonnegative in a suitable sense, to every $Ad_{SO(n,\C)}$ invariant subset $S \subset {\bf so}(n,\C)$. For curvature…

Differential Geometry · Mathematics 2011-04-11 H. A. Gururaja , Soma Maity , Harish Seshadri

We introduce a flow of Riemannian metrics over compact manifolds with formal limit at infinite time a shrinking Ricci soliton. We call this flow the Soliton-Ricci flow. It correspond to a Perelman's modified backward Ricci type flow with…

Differential Geometry · Mathematics 2012-03-19 Nefton Pali

If a normalized K\"{a}hler-Ricci flow $g(t),t\in[0,\infty),$ on a compact K\"{a}hler $n$-manifold, $n\geq 3$, of positive first Chern class satisfies $g(t)\in 2\pi c_{1}(M)$ and has $L^{n}$ curvature operator uniformly bounded, then the…

Differential Geometry · Mathematics 2008-03-02 Wei-Dong Ruan , Yuguang Zhang , Zhenlei Zhang

Haslhofer and M\"uller proved a compactness Theorem for four-dimensional shrinking gradient Ricci solitons, with the only assumption being that the entropy is uniformly bounded from below. However, the limit in their result could possibly…

Differential Geometry · Mathematics 2017-07-20 Yongjia Zhang
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