English
Related papers

Related papers: Remarks on the Friedman equations

200 papers

Ricci flow on two dimensional surfaces is far simpler than in the higher dimensional cases. This presents an opportunity to obtain much more detailed and comprehensive results. We review the basic facts about this flow, including the…

Differential Geometry · Mathematics 2011-03-25 James Isenberg , Rafe Mazzeo , Natasa Sesum

We establish a point-wise gradient estimate for $all$ positive solutions of the conjugate heat equation. This contrasts to Perelman's point-wise gradient estimate which works mainly for the fundamental solution rather than all solutions.…

Differential Geometry · Mathematics 2007-05-23 Shilong Kuang , Qi S. Zhang

We give a survey on the Chern-Ricci flow, a parabolic flow of Hermitian metrics on complex manifolds. We emphasize open problems and new directions.

Differential Geometry · Mathematics 2022-07-12 Valentino Tosatti , Ben Weinkove

We show that the analog of Hamilton's Ricci flow in the combinatorial setting produces solutions which converge exponentially fast to Thurston's circle packing on surfaces. As a consequence, a new proof of Thurston's existence of circle…

Differential Geometry · Mathematics 2007-05-23 Bennett Chow , Feng Luo

We study the behavior of the normalized Ricci flow of invariant Riemannian homogeneous metrics at infinity for generalized Wallach spaces, generalized flag manifolds with four isotropy summands and second Betti number equal to one, and the…

Differential Geometry · Mathematics 2020-08-11 Marina Statha

This is the second paper in a series of works devoted to nonholonomic Ricci flows. By imposing non-integrable (nonholonomic) constraints on the Ricci flows of Riemannian metrics we can model mutual transforms of generalized Finsler-Lagrange…

Differential Geometry · Mathematics 2008-11-26 Sergiu I. Vacaru

We consider a normalization of the Ricci flow on a closed Riemannian manifold given by the evolution equation $\partial_{t}g(t)=-2(Ric(g(t))-\frac{1}{2\tau}g(t))$ where $\tau$ is a fixed positive number. Assuming that a solution for this…

Differential Geometry · Mathematics 2013-02-19 Antonio G. Ache

In this paper, we derive some local a priori estimates for Ricci flow. This gives rise to some strong uniqueness theorems. As a corollary, let $g(t)$ be a smooth complete solution to the Ricci flow on $\mathbb{R}^{3}$, with the canonical…

Differential Geometry · Mathematics 2010-10-06 Bing-Long Chen

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

In this paper we give an explicit bound of $\Delta_{g(t)}u(t)$ and the local curvature estimates for the Ricci-harmonic flow under the condition that the Ricci curvature is bounded along the flow. In the second part these local curvature…

Differential Geometry · Mathematics 2018-10-24 Yi Li

We give examples of pinched negatively curved manifolds for which the Ricci flow does not converge smoothly.

Differential Geometry · Mathematics 2007-05-23 F. T. Farrell , P. Ontaneda

A fundamental tool in the analysis of Ricci flow is a compactness result of Hamilton in the spirit of the work of Cheeger, Gromov and others. Roughly speaking it allows one to take a sequence of Ricci flows with uniformly bounded curvature…

Differential Geometry · Mathematics 2011-10-18 Peter Topping

There are described equations for a pair comprising a Riemannian metric and a Killing field on a surface that contain as special cases the Einstein Weyl equations (in the sense of D. Calderbank) and a real version of a special case of the…

Differential Geometry · Mathematics 2014-08-26 Daniel J. F. Fox

In this paper we study the Ricci flow on surfaces homeomorphic to a cylinder (that is, a product of the circle with a compact interval). We prove longtime existence results, results on the asymptotic behavior of the flow, and we report on…

Differential Geometry · Mathematics 2016-04-08 Jean Cortissoz , Alexander Murcia

In this paper we present some results on a family of geometric flows introduced by Bourguignon that generalize the Ricci flow. For suitable values of the scalar parameter involved in these flows, we prove short time existence and provide…

Differential Geometry · Mathematics 2017-04-25 Giovanni Catino , Laura Cremaschi , Zindine Djadli , Carlo Mantegazza , Lorenzo Mazzieri

In this paper, we establish Li-Yau-type and Hamilton-type estimates for positive solutions to the heat equation associated with the generalized Ricci flow, under a less stringent curvature condition. Compared with [25] and [35], these…

Differential Geometry · Mathematics 2025-06-06 Juanling Lu , Yu Zheng

In this paper, we give a sufficient condition such that the Ricci flow in $R^2$ exists globally and the flow converges at $t=\infty$ to the flat metric on $R^2$.

Differential Geometry · Mathematics 2011-12-30 Li Ma

In the paper, we study evolution equations of the scalar and Ricci curvatures under the Hamilton's Ricci flow on a closed manifold and on a complete noncompact manifold. In particular, we study conditions when the Ricci flow is trivial and…

Differential Geometry · Mathematics 2020-09-17 Vladimir Rovenski , Sergey Stepanov , Irina Tsyganok

In this short notes, we discuss monotonicity formulas under various rescaled versions of Ricci flow. The main result is Theorem \ref{theo rescaled}.

Differential Geometry · Mathematics 2007-11-10 Jun-Fang Li

We study the long time behaviour of Ricci flow with bubbling-off on a possibly noncompact $3$-manifold of finite volume whose universal cover has bounded geometry. As an application, we give a Ricci flow proof of Thurston's hyperbolisation…

Differential Geometry · Mathematics 2014-05-22 Laurent Bessières , Gérard Besson , Sylvain Maillot