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We verify a conjecture of Perelman, which states that there exists a canonical Ricci flow through singularities starting from an arbitrary compact Riemannian 3-manifold. Our main result is a uniqueness theorem for such flows, which,…

Differential Geometry · Mathematics 2018-04-19 Richard H. Bamler , Bruce Kleiner

$\mathscr{W}$-entropy and reduced volume for the Ricci flow were introduced by Perelman, which had proved their importance in the study of the Ricci flow. L. Ni studied the analogous concepts for the linear heat equation on the static…

Differential Geometry · Mathematics 2017-05-30 Guoyi Xu

I survey some of the developments in the theory of Ricci flow and its applications from the past decade. I focus mainly on the understanding of Ricci flows that are permitted to have unbounded curvature in the sense that the curvature can…

Differential Geometry · Mathematics 2020-05-07 Peter M. Topping

We investigate the properties of the combinatorial Ricci flow for surfaces, both forward and backward -- existence, uniqueness and singularities formation. We show that the positive results that exist for the smooth Ricci flow also hold for…

Differential Geometry · Mathematics 2011-06-09 Emil Saucan

We explore the harmonic-Ricci flow---that is, Ricci flow coupled with harmonic map flow---both as it arises naturally in certain principal bundle constructions related to Ricci flow and as a geometric flow in its own right. We demonstrate…

Differential Geometry · Mathematics 2012-12-18 Michael Bradford Williams

We analyse Ricci flow (normalised/un-normalised) of product manifolds --unwarped as well as warped, through a study of generic examples. First, we investigate such flows for the unwarped scenario with manifolds of the type $\mathbb…

General Relativity and Quantum Cosmology · Physics 2011-05-09 Sanjit Das , Kartik Prabhu , Sayan Kar

We show how solutions to the Ricci flow on Lorentzian manifolds, along with its generalizations, can be linked to Einstein's field equations. The approach involves deformations of the matter sector that are generated by quadratic…

High Energy Physics - Theory · Physics 2024-11-18 Tommaso Morone , Roberto Tateo

We formulate a statistical analogy of regular Lagrange mechanics and Finsler geometry derived from Grisha Perelman's functionals generalized for nonholonomic Ricci flows. There are elaborated explicit constructions when nonholonomically…

Differential Geometry · Mathematics 2015-06-26 Sergiu I. Vacaru

In this work, we obtain some existence results of Chern-Ricci Flows and the corresponding Potential Flows on complex manifolds with possibly incomplete initial data. We discuss the behaviour of the solution as $t\rightarrow 0$. These…

Differential Geometry · Mathematics 2019-08-16 Shaochuang Huang , Man-Chun Lee , Luen-Fai Tam

We construct the classical mechanics associated with a conformally flat Riemannian metric on a compact, n-dimensional manifold without boundary. The corresponding gradient Ricci flow equation turns out to equal the time-dependent…

High Energy Physics - Theory · Physics 2009-10-16 S. Abraham , P. Fernandez de Cordoba , J. M. Isidro , J. L. G. Santander

We prove that on ALF $n$-manifolds with $n\ge 4$ the Ricci flow preserves the ALF structure, and develop a weighted Fredholm framework adapted to ALF manifolds. Motivated by Perelman's $\lambda$-functional, we define a renormalized…

Differential Geometry · Mathematics 2025-10-28 Dain Kim , Tristan Ozuch

We give the global picture of the normalized Ricci flow on generalized flag manifolds with two or three isotropy summands. The normalized Ricci flow for these spaces descents to a parameter depending system of two or three ordinary…

Differential Geometry · Mathematics 2011-05-25 Stavros Anastassiou , Ioannis Chrysikos

This book gives an introduction to fundamental aspects of generalized Riemannian, complex, and K\"ahler geometry. This leads to an extension of the classical Einstein-Hilbert action, which yields natural extensions of Einstein and…

Differential Geometry · Mathematics 2020-08-31 Mario Garcia-Fernandez , Jeffrey Streets

We establish the short-time existence of the Ricci flow on surfaces with a finite number of conic points, all with cone angle between 0 and $2\pi$, where the cone angles remain fixed or change in some smooth prescribed way. For the…

Differential Geometry · Mathematics 2015-07-29 Rafe Mazzeo , Yanir A. Rubinstein , Natasa Sesum

We review different notions of synthetic Ricci flow that apply to time-dependent families of metric measure spaces and which are based on properties of the heat flow, ideas from optimal transport, and the asymptotic behaviour of volumes.…

Differential Geometry · Mathematics 2025-11-17 Matthias Erbar , Marco Flaim , Eric Hupp , Zhenhao Li , Timo Schultz , Karl-Theodor Sturm

We develop different synthetic notions of Ricci flow in the setting of time-dependent metric measure spaces based on ideas from optimal transport. They are formulated in terms of dynamic convexity and local concavity of the entropy along…

Differential Geometry · Mathematics 2025-01-14 Matthias Erbar , Zhenhao Li , Timo Schultz

In this article we derive gradient estimation for positive solution of the equation \begin{equation*} (\partial_t-\Delta_f)u = A(u)p(x,t) + B(u)q(x,t) + \mathcal{G}(u) \end{equation*} on a weighted Riemannian manifold evolving along the…

Differential Geometry · Mathematics 2025-01-17 Yanlin Li , Abimbola Abolarinwa , Suraj Ghosh , Shyamal Kumar Hui

We introduce the notion of Canonical Expanding Ricci Soliton, and use it to derive new Harnack inequalities for Ricci flow. This viewpoint also gives geometric insight into the existing Harnack inequalities of Hamilton and Brendle.

Differential Geometry · Mathematics 2009-11-30 Esther Cabezas-Rivas , Peter M. Topping

Using double 2+2 and 3+1 nonholonomic fibrations on Lorentz manifolds, we extend the concept of W-entropy for gravitational fields in the general relativity, GR, theory. Such F- and W-functionals were introduced in the Ricci flow theory of…

General Relativity and Quantum Cosmology · Physics 2017-03-28 Vyacheslav Ruchin , Olivia Vacaru , Sergiu I. Vacaru

In this paper we will give a simple proof of a modification of a result on pseudolocality for the Ricci flow by P.Lu without using the pseudolocality theorem 10.1 of Perelman [P1]. We also obtain an extension of a result of Hamilton on the…

Differential Geometry · Mathematics 2010-10-07 Shu-Yu Hsu
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