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Related papers: Remarks on the Friedman equations

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This is a continuation of the research in [16]. Let $(\overline{M},g_{-1})$ be a closed geodesic $r_0$-ball in the hyperbolic space $(\mathbb{H}^n,g_{-1})$. Let $m\neq1$ be a positive constant. In this paper, we show that for $n\geq3$,…

Differential Geometry · Mathematics 2026-05-13 Gang Li

We will give some regularity results about fractional diffusion-wave equations.

Analysis of PDEs · Mathematics 2021-08-10 Paola Loreti , Daniela Sforza

In this paper, we consider solutions of the backward heat equation with Ricci flow on manifolds as a type of infinite dimensional limit of solutions of a wave equation on a larger manifold with an analysis of wavefront set. Specifically,…

Differential Geometry · Mathematics 2020-02-07 Jie Xu

We prove pinching estimates for solutions of the linearized Ricci flow system on a closed manifold of dimension $n\geq 4$ with positive scalar curvature and vanishing Weyl tensor. If the vanishing Weyl tensor condition is removed, we only…

Differential Geometry · Mathematics 2016-02-19 Jia-Yong Wu , Jian-Biao Chen

We study the Ricci-Bourguignon flow on warped product manifolds with noncompact base. This setting leads naturally to a parabolic partial differential equation on the space of smooth warping functions, arising from the necessary and…

Differential Geometry · Mathematics 2026-04-17 José N. V. Gomes , Willian I. Tokura , Hikaru Yamamoto

In this paper, we study curvature behavior at the first singular time of solution to the Ricci flow on a smooth, compact n-dimensional Riemannian manifold $M$, $\frac{\partial}{\partial t}g_{ij} = -2R_{ij}$ for $t\in [0,T)$. If the flow has…

Differential Geometry · Mathematics 2010-05-31 Nam Q. Le , Natasa Sesum

We show that any noncompact Riemann surface admits a complete Ricci flow g(t), t\in[0,\infty), which has unbounded curvature for all t\in[0,\infty).

Analysis of PDEs · Mathematics 2013-02-19 Gregor Giesen , Peter M. Topping

Using a recently developed piecewise flat method, numerical evolutions of the Ricci flow are computed for a number of manifolds, using a number of different mesh types, and shown to converge to the expected smooth behaviour as the mesh…

Differential Geometry · Mathematics 2024-02-26 Rory Conboye

Let $(M^3,g_0)$ be a complete noncompact Riemannian 3-manifold with nonnegative Ricci curvature and with injectivity radius bounded away from zero. Suppose that the scalar curvature $R(x)\to 0$ as $x\to \infty$. Then the Ricci flow with…

Differential Geometry · Mathematics 2008-07-07 Hong Huang

In \cite{P1}, Perelman established a differential Li-Yau-Hamilton (LYH) type inequality for fundamental solutions of the conjugate heat equation corresponding to the Ricci flow on compact manifolds (also see \cite{N2}). As an application of…

Differential Geometry · Mathematics 2007-05-23 Albert Chau , Luen-Fai Tam , Chengjie Yu

We consider the asymptotic behavior of the normalized Ricci flow on generalized Wallach spaces that could be considered as special planar dynamical systems. All non symmetric generalized Wallach spaces can be naturally parametrized by three…

Differential Geometry · Mathematics 2016-02-17 N. A. Abiev , A. Arvanitoyeorgos , Yu. G. Nikonorov , P. Siasos

In this paper we consider the Ricci flow on manifolds with boundary with appropriate control on its mean curvature and conformal class. We obtain higher order estimates for the curvature and second fundamental form near the boundary,…

Differential Geometry · Mathematics 2016-11-07 Panagiotis Gianniotis

The first part of the paper discusses a second-order quasilinear parabolic equation in a vector bundle over a compact manifold $M$ with boundary $\partial M$. We establish a short-time existence theorem for this equation. The second part of…

Analysis of PDEs · Mathematics 2013-11-08 Artem Pulemotov

We present a Friedmann-Robertson-Walker (FRW) quantum cosmological model within the framework of Finslerian geometry. In this work, we consider a specific fluid. We obtain the corresponding Wheeler-DeWitt equation as the usual constraint…

General Physics · Physics 2019-11-04 S S De , Farook Rahaman , Nupur Paul

We give a geometric interpretation of the linear trace Harnack inequality for the Ricci flow.

Differential Geometry · Mathematics 2007-05-23 Bennett Chow , Sun-Chin Chu

In this survey we review Hamilton's entropy and Perelman's entropy, and provide motivations for these concepts. Then we review recent results on the logarithmic Sobolev inequality, the Sobolev inequalities and kappa-noncollapsing estimates…

Differential Geometry · Mathematics 2007-09-19 Rugang Ye

We show that an orientable 3-dimensional manifold M admits a complete riemannian metric of bounded geometry and uniformly pos- itive scalar curvature if and only if there exists a finite collection F of spherical space-forms such that M is…

Differential Geometry · Mathematics 2014-11-11 Laurent Bessières , Gérard Besson , Sylvain Maillot

We establish a short-time existence theory for complete Ricci flows under scaling-invariant curvature bounds, starting from rotationally symmetric metrics on $\mathbb{R}^{n+1}$ that are noncollapsed at infinity, without assuming bounded…

Differential Geometry · Mathematics 2025-05-30 Ming Hsiao

In this note, we prove some new entropy formula for linear heat equation on static Riemannian manifold with nonnegative Ricci curvature. The results are analogies of Cao and Hamilton's entropies for Ricci flow coupled with heat-type…

Differential Geometry · Mathematics 2022-07-29 Yucheng Ji

The hydrodynamic model for the expansion of the fireball in relativistic heavy-ion collisions is presented. Calculations using relativistic hydrodynamics of a fluid with small viscosity yield a satisfactory description of the experimental…

Nuclear Theory · Physics 2012-06-18 Piotr Bozek