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Related papers: Examples of flag-wise positively curved spaces

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We show that the minimal hypersurface method of Schoen and Yau can be used for the ``quantitative'' study of positive scalar curvature. More precisely, we show that if a manifold admits a metric $g$ with $s_g \ge | T |$ or $s_g \ge | W |$,…

Differential Geometry · Mathematics 2008-01-02 Harish Seshadri

A Finsler space $(M,F)$ is called a geodesic orbit space if any geodesic of constant speed is the orbit of a one-parameter subgroup of isometries of $(M, F)$. In this paper, we study Finsler metrics on Euclidean spaces which are geodesic…

Differential Geometry · Mathematics 2018-10-12 Ming Xu , Shaoqiang Deng , Zaili Yan

Is a sequence of Riemannian manifolds with positive scalar curvature, satisfying some conditions to keep the sequence reasonable, compact? What topology should one use for the convergence and what is the regularity of the limit space? In…

Differential Geometry · Mathematics 2024-06-07 Brian Allen , Wenchuan Tian , Changliang Wang

We give a lower bound for the length of a non-trivial geodesic loop on a simply-connected and compact manifold of even dimension with a non-reversible Finsler metric of positive flag curvature. Harris and Paternain use this estimate in…

Differential Geometry · Mathematics 2007-06-01 Hans-Bert Rademacher

The aim of this article is to establish a Toponogov type triangle comparison theorem for Finsler manifolds, in the manner of radial curvature geometry. We consider the situation that the radial flag curvature is bounded below by the radial…

Differential Geometry · Mathematics 2013-09-17 Kei Kondo , Shin-ichi Ohta , Minoru Tanaka

As was recently observed by M. Xu and J. Wolf, there is a gap in Berard Bergery's classification of odd dimensional positively curved homogeneous spaces. Since this classification has been used in other papers as well, we give a modern,…

Differential Geometry · Mathematics 2015-03-24 Burkhard Wilking , Wolfgang Ziller

In this paper, we show that any compact K$\"a$hler manifold homotopic to a compact Riemannian manifold with negative sectional curvature admits a K$\"a$hler-Einstein metric of general type. Moreover, we prove that, on a compact symplectic…

Differential Geometry · Mathematics 2017-11-10 Bing-Long Chen , Xiaokui Yang

We classify the triples $H \subset K \subset G$ of nested compact Lie groups which satisfy the "positive triple" condition that was shown by the second author to ensure that $G/H$ admits a metric with quasi-positive curvature. A few new…

Differential Geometry · Mathematics 2012-11-19 Megan M. Kerr , Kristopher Tapp

We prove that a 2n-dimensional compact homogeneous nearly Kahler manifold with strictly positive sectional curvature is isometric to CP^{n}, equipped with the symmetric Fubini-Study metric or with the standard Sp(m)-homogeneous metric, n…

Differential Geometry · Mathematics 2009-04-06 J. C. Gonzalez Davila , F. Martin Cabrera

In this paper we consider invariant Matsumoto metrics which are induced by invariant Riemannian metrics and invariant vector fields on homogeneous spaces then we give the flag curvature formula of them. Also we study the special cases of…

Differential Geometry · Mathematics 2015-07-09 H. R. Salimi Moghaddam

The sharpness of various Hardy-type inequalities is well-understood in the reversible Finsler setting; while infinite reversibility implies the failure of these functional inequalities, cf. Krist\'aly, Huang, and Zhao [Trans. Am. Math.…

Analysis of PDEs · Mathematics 2026-01-14 Sándor Kajántó

Our goal is to identify curvature conditions that distinguish Euclidean space in the case of open, contractible manifolds and the disk in the case of compact, contractible manifolds with boundary. First, we show that an open manifold that…

Differential Geometry · Mathematics 2025-07-22 Paul Sweeney

Suppose that $(M,\mathfrak{g})$ is a compact Riemannian manifold with strictly negative sectional curvatures. A subset of conjugacy classes $E \subset \text{conj}(\pi_1(M))$ is called spectrally rigid if when two negatively curved…

Dynamical Systems · Mathematics 2025-06-09 Stephen Cantrell

We study a special class of Finsler metrics which we refer to as Almost Rational Finsler metrics (shortly, AR-Finsler metrics). We give necessary and sufficient conditions for an AR-Finsler manifold $(M,F)$ to be Riemannian. The rationality…

Differential Geometry · Mathematics 2024-07-02 Ebtsam H. Taha , Bankteshwar Tiwari

Manifolds admitting positive sectional curvature are conjectured to have rigid homotopical structure and, in particular, comparatively small Euler charateristics. In this article, we obtain upper bounds for the Euler characteristic of a…

Differential Geometry · Mathematics 2014-07-22 Manuel Amann , Lee Kennard

We define a partition of the space of projectively flat metrics in three classes according to the sign of the Chern scalar curvature; we prove that the class of negative projectively flat metrics is empty, and that the class of positive…

Differential Geometry · Mathematics 2021-03-25 Simone Calamai

A flag area measure on an $n$-dimensional euclidean vector space is a continuous translation-invariant valuation with values in the space of signed measures on the flag manifold consisting of a unit vector $v$ and a $(p+1)$-dimensional…

Differential Geometry · Mathematics 2019-07-24 Judit Abardia-Evéquoz , Andreas Bernig , Susanna Dann

The development of projective invariant Weyl metrics in this paper offers a fresh perspective, as we establish the characteristics of both weakly-Weyl and generalized weakly-Weyl Finsler metrics. We thoroughly examine the connections…

Differential Geometry · Mathematics 2025-11-11 Nasrin Sadeghzadeh , Meshkat Yavari

This paper studies a specific metric on plane curves that has the property of being isometric to classical manifold (sphere, complex projective, Stiefel, Grassmann) modulo change of parametrization, each of these classical manifolds being…

Differential Geometry · Mathematics 2008-05-05 Peter W. Michor , David Mumford , Jayant Shah , Laurent Younes

We provide techniques for studying the nonnegatively curved left-invariant metrics on a compact Lie group. For "straight" paths of left-invariant metrics starting at bi-invariant metrics and ending at nonnegatively curved metrics, we deduce…

Differential Geometry · Mathematics 2007-05-23 Jack Huizenga