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We present two characterizations of smooth compact Ricci flow solutions solely in terms of metrics and measures (one of them only works under positive scalar curvature along the flow); thus, provide weak formulations that are generalized to…

Differential Geometry · Mathematics 2026-04-14 Sajjad Lakzian

We establish a 1-to-1 relation between metrics on compact Riemann surfaces without boundary, and mechanical systems having those surfaces as configuration spaces.

High Energy Physics - Theory · Physics 2010-02-10 S. Abraham , P. Fernandez de Cordoba , J. M. Isidro , J. L. G. Santander

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

In this note we explain how a flow in the space of Riemmanian metrics (including Ricci's \cite{mt}) induces one in the space of pseudoconnections.

Differential Geometry · Mathematics 2015-09-28 C. A. Morales

If we want to deform a compact Riemannian manifold with boundary using Ricci flow, we first need to decide on appropriate boundary conditions. We would like these conditions to reflect the geometric nature of the flow and allow for a…

Differential Geometry · Mathematics 2024-03-15 Rasmus Jouttijärvi

This is the first of a series of papers, where we introduce a new class of estimates for the Ricci flow, and use them both to characterize solutions of the Ricci flow and to provide a notion of weak solutions to the Ricci flow in the…

Differential Geometry · Mathematics 2015-04-06 Robert Haslhofer , Aaron Naber

In this paper we construct a version of Ricci flow for noncommutative 2-tori, based on a spectral formulation in terms of the eigenvalues and eigenfunction of the Laplacian and recent results on the Gauss-Bonnet theorem for noncommutative…

High Energy Physics - Theory · Physics 2015-05-28 Tanvir Ahamed Bhuyain , Matilde Marcolli

We study the Ricci flow on Riemannian groupoids. We assume that these groupoids are closed and that the space of orbits is compact and connected. We prove the short time existence and uniqueness of the Ricci flow on these groupoids. We also…

Differential Geometry · Mathematics 2015-07-28 Christian Hilaire

This is the first of a series of papers on the long-time behavior of 3 dimensional Ricci flows with surgery. In this paper we first fix a notion of Ricci flows with surgery, which will be used in this and the following three papers. Then we…

Differential Geometry · Mathematics 2018-03-16 Richard H. Bamler

In this paper, we establish a framework for the analysis of linear parabolic equations on conical surfaces and use them to study the conical Ricci flow. In particular, we prove the long time existence of the conical Ricci flow for general…

Analysis of PDEs · Mathematics 2016-05-31 Hao Yin

Using a continuous unitary transformation recently proposed by Wegner \cite{Wegner} together with an approximation that neglects irrelevant contributions, we obtain flow equations for Hamiltonians. These flow equations yield a diagonal or…

Condensed Matter · Physics 2009-10-22 Stephan Kehrein , Andreas Mielke

The Ricci flow on the 2-sphere with marked points is shown to converge in all three stable, semi-stable, and unstable cases. In the stable case, the flow was known to converge without any reparametrization, and a new proof of this fact is…

Differential Geometry · Mathematics 2014-07-07 D. H. Phong , Jian Song , Jacob Sturm , Xiaowei Wang

The present work extends the application of a modified Ricci flow equation to an asymptotically non flat space, namely Marder's cylindrially symmetric space. It is found that the flow equation has a solution at least in a particular case.

General Relativity and Quantum Cosmology · Physics 2015-06-15 Shubhayu Chatterjee , Narayan Banerjee

We provide a proof that nonholonomically constrained Ricci flows of (pseudo) Riemannian metrics positively result into nonsymmetric metrics (as explicit examples, we consider flows of some physically valuable exact solutions in general…

General Relativity and Quantum Cosmology · Physics 2009-02-18 Sergiu I. Vacaru

I discuss certain applications of the Ricci flow in physics. I first review how it arises in the renormalization group (RG) flow of a nonlinear sigma model. I then review the concept of a Ricci soliton and recall how a soliton was used to…

High Energy Physics - Theory · Physics 2009-11-13 E. Woolgar

This paper defines a parabolic frequency for solutions of the heat equation on a Ricci flow and proves it's monotonicity along the flow. Frequency monotonicity is known to have many useful consequences; here it is shown to provide a simple…

Differential Geometry · Mathematics 2022-08-01 Julius Baldauf , Dain Kim

This survey reviews some facts about nonnegativity conditions on the curvature tensor of a Riemannian manifold which are preserved by the action of the Ricci flow. The text focuses on two main points. First we describe the known examples of…

Differential Geometry · Mathematics 2014-11-21 Thomas Richard

We present some recent results on the existence of solutions of the Schr\"odinger flows, and pose some problems for further research.

Analysis of PDEs · Mathematics 2007-05-23 Weiyue Ding

We develop a theory of Ricci flow for metrics on Courant algebroids which unifies and extends the analytic theory of various geometric flows, yielding a general tool for constructing solutions to supergravity equations. We prove short time…

Differential Geometry · Mathematics 2024-02-20 Jeffrey Streets , Charles Strickland-Constable , Fridrich Valach

In a recent article, Faraoni proposed an alternative procedure to solve the Friedman-Lemaitre-Robertson-Walker (FLRW) cosmological equations. The basic result of that paper was obtained long ago through a different approach, which seems to…

Astrophysics · Physics 2015-06-24 J. A. S. Lima