English
Related papers

Related papers: A Class of Kaehler Einstein Structures on the Nonz…

200 papers

The aim of this paper is to study Seifert bundle structures on simply connected 5--manifolds. We classify all such 5--manifolds which admit a Seifert bundle structure, and in a few cases all Seifert bundle structures are also classified.…

Differential Geometry · Mathematics 2007-05-23 János Kollár

We construct new homogeneous Einstein spaces with negative Ricci curvature in two ways: First, we give a method for classifying and constructing a class of rank one Einstein solvmanifolds whose derived algebras are two-step nilpotent. As an…

Differential Geometry · Mathematics 2007-05-23 Carolyn S. Gordon , Megan M. Kerr

We develop a geometric and explicit construction principle that generates classes of Poincare-Einstein manifolds, and more generally almost Einstein manifolds. Almost Einstein manifolds satisfy a generalisation of the Einstein condition;…

Differential Geometry · Mathematics 2008-08-18 A. Rod Gover , Felipe Leitner

We show that a compact quaternionic-K\"ahler manifold with positive scalar curvature and nonnegative sectional curvature is isometric to a symmetric space. This extends a classical theorem of Berger.

Differential Geometry · Mathematics 2025-06-30 S. Brendle , U. Semmelmann

Any $6$-dimensional strict nearly K\"ahler manifold is Einstein with positive scalar curvature. We compute the coindex of the metric with respect to the Einstein-Hilbert functional on each of the compact homogeneous examples. Moreover, we…

Differential Geometry · Mathematics 2022-08-25 Paul Schwahn

We prove that a compact Einstein manifold of dimension $n\geq 4$ with nonnegative curvature operator of the second kind is a constant curvature space by Bochner technique. Moreover, we obtain that compact Einstein manifolds of dimension…

Differential Geometry · Mathematics 2023-12-01 Zhi-Lin Dai , Hai-Ping Fu

We classify both local and global K\"ahler structures admitting totally geodesic homothetic foliations with complex leaves. The main building blocks are related to Swann's twists and are obtained by applying Weinstein's method of…

Differential Geometry · Mathematics 2025-05-26 Paul-Andi Nagy , Liviu Ornea

We construct a compact K\"ahler manifold of nonnegative quadratic bisectional curvature, which does not admit any K\"ahler metric of nonnegative orthogonal bisectional curvature. The manifold is a 7-dimensional K\"ahler C-space with second…

Differential Geometry · Mathematics 2011-10-11 Qun Li , Damin Wu , Fangyang Zheng

For moduli space of stable parabolic bundles on a compact Riemann surface, we derive an explicit formula for the curvature of its canonical line bundle with respect to Quillen's metric and interpret it as a local index theorem for the…

Algebraic Geometry · Mathematics 2015-01-12 Leon A. Takhtajan , Peter G. Zograf

In this paper, we give some simple conditions under which a Hamiltonian stationary Lagrangian submanifold of a K\"ahler-Einstein manifold must have a Euclidean factor or be a fiber bundle over a circle. We also characterize the Hamiltonian…

Differential Geometry · Mathematics 2024-08-15 Patrik Coulibaly

We describe a construction of Riemannian metrics of nonnegative sectional curvature on a closed smooth nonorientable 4-manifold with fundamental group of order two that realizes a homotopy class that was not previously known to contain…

Differential Geometry · Mathematics 2018-12-14 Rafael Torres

We compute a Bochner type formula for static three-manifolds and deduce some applications in the case of positive scalar curvature. We also explain in details the known general construction of the (Riemannian) Einstein (n+1)-manifold…

Differential Geometry · Mathematics 2015-03-13 L. Ambrozio

A Riemannian or pseudo-Riemannian (or conformal) structure is conformally Einstein if and only if there is a suitably generic parallel section of a certain vector bundle -- the so-called standard conformal tractor bundle. We show that this…

Differential Geometry · Mathematics 2007-05-23 A. R. Gover

In this article, we propose the following conjecture: if the Strominger connection of a compact Hermitian manifold has constant non-zero holomorphic sectional curvature, then the Hermitian metric must be K\"ahler. The main result of this…

Differential Geometry · Mathematics 2023-02-24 Shuwen Chen , Fangyang Zheng

This paper is concerned with the construction of special metrics on non-compact 4-manifolds which arise as resolutions of complex orbifold singularities. Our study is close in spirit to the construction of the hyperkaehler gravitational…

Differential Geometry · Mathematics 2015-06-26 David M. J. Calderbank , Michael A. Singer

Let $M$ be a Kaehler manifold, and consider the total space $T^*M$ of the cotangent bundle to $M$. We show that in the formal neighborhood of the zero section $M \subset T^*M$ the space $T^*M$ admits a canonical hyperkaehler structure,…

alg-geom · Mathematics 2007-05-23 D. Kaledin

Given a positive integer $n$ and a compact connected Riemann surface $X$, we prove that the symmetric product $S^n(X)$ admits a Kaehler form of nonnegative holomorphic bisectional curvature if and only if $\text{genus}(X) \leq 1$. If $n$ is…

Algebraic Geometry · Mathematics 2012-03-02 Indranil Biswas

We show uniqueness up to sign of positive, orthogonal almost-Kaehler structures on any non-scalar flat Kaehler-Einstein surface.

Differential Geometry · Mathematics 2012-08-09 A. J. diScala , Paul-Andi Nagy

We show that all compact quasi-Einstein metrics of constant scalar curvature in dimension three are locally homogeneous. We accomplish this by using the equivalence of constant scalar curvature quasi-Einstein metrics $(M,g,X)$ and…

Differential Geometry · Mathematics 2025-12-24 Eric Cochran

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