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Related papers: Bunching for relatively pinched metrics

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We prove weak convergence of curvature tensors of Riemannian manifolds for converging noncollapsing sequences with a lower bound on sectional curvature.

Differential Geometry · Mathematics 2024-12-25 Nina Lebedeva , Anton Petrunin

A. Derdzinki [D] gave examples of Riemannian metrics with harmonic curvature and non parallel Ricci tensor on some compact manifolds $(M,g]$ . We examine their existence as well as their number wich naturally depends on the geometry of the…

Differential Geometry · Mathematics 2007-05-23 A. Raouf Chouikha

We study tautness properties of a Riemannian foliation by investigating a symmetric 2-tensor associated with the mean curvature of the foliation. As a consequence, we prove a tautness condition for Riemannian foliations on compact manifolds…

Differential Geometry · Mathematics 2026-05-26 Jungwoo Moon

We prove that compact K\"ahler manifolds whose sectional curvatures are close to 1/4-pinched have ratios of Chern numbers close to the corresponding ratios of a complex hyperbolic space form. We deduce that the Mostow-Siu surfaces (and…

Differential Geometry · Mathematics 2011-04-14 Martin Deraux , Harish Seshadri

In this paper, we investigate the geometry of Einstein-type equation on a Riemannian manifold, unifying various particular geometric structures recently studied in the literature, such as critical point equation and vacuum static equation.…

Differential Geometry · Mathematics 2022-03-31 Gabjin Yun , Seungsu Hwang

For a compact K\"{a}hler-Einstein manifold $M$ of dimension $n\ge 2$, we explicitly write the expression $-c_1^n(M)+\frac{2(n+1)}{n}c_2(M)c_1^{n-2}(M)$ in the form of certain integral on the holomorphic sectional curvature and its average…

Differential Geometry · Mathematics 2025-03-25 Rong Du

We study unimodular measures on the space $\mathcal M^d$ of all pointed Riemannian $d$-manifolds. Examples can be constructed from finite volume manifolds, from measured foliations with Riemannian leaves, and from invariant random subgroups…

Geometric Topology · Mathematics 2022-12-21 Miklos Abert , Ian Biringer

We use certain Morse functions to construct conformal metrics such that the eigenvalue vector of modified Schouten tensor belongs to a given cone. As a result, we prove that any Riemannian metric on compact 3-manifolds with boundary is…

Differential Geometry · Mathematics 2023-08-14 Rirong Yuan

In this note we shall show that the sectional curvature of a harmonic manifold is bounded on both sides. In fact we shall give a pinching constant for all harmonic manifolds. We shall use the imbedding theorem for harmonic manifolds proved…

dg-ga · Mathematics 2008-02-03 K. Ramachandran , Akhil Ranjan

Some curvature estimates are derived from geometrical data concerning quasi-conformality properties of some commuting linearly independent vector fields on a compact Riemannian manifold.

dg-ga · Mathematics 2008-02-03 Pawel Walczak

This paper connects nonpositive sectional curvature of a Riemannian manifold with the displacement convexity of the variance functional on the space $P(M)$ of probability measures over $M$. We show that $M$ has nonpositive sectional…

Differential Geometry · Mathematics 2015-03-24 Young-Heon Kim , Brendan Pass

We consider the problem of conformally deforming a metric to one with a prescribed symmetric function of the eigenvalues of the Ricci tensor, in the case of negative curvature.

Differential Geometry · Mathematics 2016-09-07 Matthew Gursky , Jeff Viaclovsky

Using Seiberg-Witten theory, it is shown that any Kaehler metric of constant negative scalar curvature on a compact 4-manifold M minimizes the L^2-norm of scalar curvature among Riemannian metrics compatible with a fixed decomposition…

dg-ga · Mathematics 2008-02-03 Claude LeBrun

In this paper, using special metric deformations introduced by Aubin, we construct Riemannian metrics satisfying non-vanishing conditions concerning the Weyl tensor, on every compact manifold. In particular, in dimension four, we show that…

Differential Geometry · Mathematics 2024-09-12 Giovanni Catino , Davide Dameno , Paolo Mastrolia

This paper is devoted to the study of a problem arising from a geometric context, namely the conformal deformation of a Riemannian metric to a scalar flat one having constant mean curvature on the boundary. By means of blow-up analysis…

Analysis of PDEs · Mathematics 2007-05-23 Veronica Felli , Mohameden Ould Ahmedou

We show that if a closed manifold of dimension at least four admits a negatively curved metric that is almost Einstein in a suitable sense, then it admits a genuine Einstein metric of negative sectional curvature. Importantly, the pinching…

Differential Geometry · Mathematics 2025-12-30 Frieder Jäckel

On the symmetrized bidisc G2 with the Bergman metric, the holomorphic sectional curvature is negatively pinched and the holomorphic bisectional curvature is not. The consequences in invariant metrics are provided.

Differential Geometry · Mathematics 2022-04-26 Gunhee Cho , Yuan Yuan

This article surveys results for Riemannian manifolds of positive and non-negative sectional curvature with symmetries.

Differential Geometry · Mathematics 2023-03-21 Catherine Searle

The first variant of this article contained a fatal error. Therefore, we publish second version our paper. In the present paper, we prove that the curvature operator of the second kind of a Riemannian manifold is strictly positive if its…

Differential Geometry · Mathematics 2023-08-28 S. E. Stepanov

The goal of this paper is to investigate the rigidity of 4-dimensional manifolds involving some pinching curvature conditions. To this end, we make use of the approach of biorthogonal curvature which is weaker than the sectional curvature.…

Differential Geometry · Mathematics 2017-01-10 Ernani Ribeiro