搜索结果: 1-15 共查到“几何学 THE RICCI”相关记录28条 . 查询时间(0.265 秒)
Academy of Mathematics and Systems Science, CAS Colloquia & Seminars：Geometry of the Ricci flow singularity models
利玛窦流 奇点模型 几何形状
2023/4/25
The Ricci flow is a powerful tool in geometry to construct the canonical metric on a given manifold. It can be viewed as a nonlinear heat flow of the Riemannian metric and may develop finite time sing...
FIRST EIGENVALUES OF GEOMETRIC OPERATORS UNDER THE RICCI FLOW
GEOMETRIC OPERATORS UNDER FLOW
2015/8/17
In this paper, we prove that the first eigenvalues of
−∆ + cR (c ≥
1
4
) is nondecreasing under the Ricci flow. We also
prove the monotonicity under the normalized Ricci &...
Compact Gradient Shrinking Ricci Solitons with Positive Curvature Operator
Positive Curvature Operator Shrinking Ricci Solitons
2015/8/17
In this paper, we first derive several identities on a compact shrinking Ricci
soliton. We then show that a compact gradient shrinking soliton must be
Einstein, if it admits a Riemannian metri...
《Ricci Flow and the Sphere Theorem》。
Local pinching estimates in 3-dim Ricci flow
Local pinching estimates 3-dim Ricci flow Differential Geometry
2012/6/30
We study curvature pinching estimates of Ricci flow on complete 3- dimensional manifolds without bounded curvature assumption. We will derive some general curvature conditions which are preserved on a...
Ricci surfaces
minimal surfaces Ricci condition generalized Killing spinors Ricci surfaces
2012/6/29
A Ricci surface is a Riemannian 2-manifold $(M,g)$ whose Gaussian curvature $K$ satisfies $K\Delta K+g(dK,dK)+4K^3=0$. Every minimal surface isometrically embedded in $\mathbb{R}^3$ is a Ricci surface...
Remarks on the extension of the Ricci flow
Remarks the extension of the Ricci flow Differential Geometry
2012/6/19
We present two new conditions to extend the Ricci flow on a compact manifold over a finite time, which are improvements of some known extension theorems.
New logarithmic Sobolev inequalities and an ε-regularity theorem for the Ricci flow
New logarithmic Sobolev inequalities ε-regularity theorem Ricci flow Differential Geometry
2012/5/24
In this note we prove a new \epsilon-regularity theorem for the Ricci flow. Let (M^n,g(t)) with t\in [-T,0] be a Ricci flow and H_{x} the conjugate heat kernel centered at a point (x,0) in the final t...
No breathers theorem for some noncompact Ricci flows
No breathers theorem noncompact Ricci flows Differential Geometry
2012/5/24
Under suitable conditions near infinity and assuming boundedness of curvature tensor, we prove a no breathers theorem in the spirit of Ivey-Perelman for some noncompact Ricci flows. These include Ricc...
A note on Canonical Ricci forms on 2-step nilmanifolds
note Canonical Ricci forms 2-step nilmanifolds
2012/2/29
In this note we prove that any left-invariant almost Hermitian structure on a 2-step nilmanifold is Ricci-flat with respect to the Chern connection and that it is Ricci -flat with respect to another c...
Abstract: We simplify and improve the curvature estimates in the paper: On the conditions to extend Ricci flow(II). Furthermore, we develop some volume estimates for the Ricci flow with bounded scalar...
Abstract: We develop some estimates under the Ricci flow and use these estimates to study the blowup rates of curvatures at singularities. As applications, we obtain some gap theorems:
$\displaystyl...
Bach-flat gradient steady Ricci solitons
Bach-flat gradient Ricci solitons Differential Geometry
2011/9/19
Abstract: In this paper we prove that any $n$-dimensional ($n\ge 4$) complete Bach-flat gradient steady Ricci solitons with positive Ricci curvature is isometric to the Bryant soliton. We also show th...
Bounds on volume growth of geodesic balls under Ricci flow
geodesic balls under Ricci flow Differential Geometry Analysis of PDEs
2011/9/16
Abstract: We prove a so called $\kappa$ non-inflating property for Ricci flow, which provides an upper bound for volume ratio of geodesic balls over Euclidean ones, under an upper bound for scalar cur...
Supremum of Perelman's entropy and Kahler-Ricci flow on a Fano manifold
Kahler-Ricci flow Kahler-Ricci solitons Perelman entropy
2011/9/15
Abstract: In this paper, we extend the method in [TZhu5] to study the energy level $L(\cdot)$ of Perelman's entropy $\lambda(\cdot)$ for K\"ahler-Ricci flow on a Fano manifold. Consequently, we first ...