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We prove that a complete K\"ahler manifold with holomorphic curvature bounded between two negative constants admits a unique complete K\"ahler-Einstein metric. We also show this metric and the Kobayashi-Royden metric are both uniformly…

Differential Geometry · Mathematics 2017-11-28 Damin Wu , Shing-Tung Yau

The main result of this note essentially is that if the base and fibers of a compact fibration carry Hermitian metrics of positive holomorphic sectional curvature, then so does the total space of the fibration. The proof is based on the use…

Differential Geometry · Mathematics 2019-07-16 Ananya Chaturvedi , Gordon Heier

We prove that a smooth complex projective threefold with a K\"ahler metric of negative holomorphic sectional curvature has ample canonical line bundle. In dimensions greater than three, we prove that, under equal assumptions, the nef…

Algebraic Geometry · Mathematics 2009-09-02 Gordon Heier , Steven S. Y. Lu , Bun Wong

In this work, we investigate compact K\"ahler manifolds with non-negative or quasi-positive mixed curvature coming from a linear combination of the Ricci and holomorphic sectional curvature, which covers various notions of curvature…

Differential Geometry · Mathematics 2024-08-27 Jianchun Chu , Man-Chun Lee , Jintian Zhu

We prove that a holomorphic line bundle on a projective manifold is pseudo-effective if and only if its degree on any member of a covering family of curves is non-negative. This is a consequence of a duality statement between the cone of…

Algebraic Geometry · Mathematics 2007-05-23 Sébastien Boucksom , Jean-Pierre Demailly , Mihai Paun , Thomas Peternell

We study how the existence of a negatively pinched K\"ahler metric on a domain in complex Euclidean space restricts the geometry of its boundary. In particular, we show that if a convex domain admits a complete K\"ahler metric, with pinched…

Complex Variables · Mathematics 2022-05-04 Filippo Bracci , Hervé Gaussier , Andrew Zimmer

The intent of this article is to study some special $n$-dimensional continua lying in products of $n$ curves. (The paper is an improved version of a portion of \cite{K-K-S}.) We show that if $X$ is a locally connected, so-called, quasi…

Geometric Topology · Mathematics 2008-02-25 A. Koyama , J. Krasinkiewicz , S. Spiez

We conjecture that any perverse sheaf on a compact aspherical K\"ahler manifold has non-negative Euler characteristic. This extends the Singer-Hopf conjecture in the K\"ahler setting. We verify the stronger conjecture when the manifold X…

Algebraic Geometry · Mathematics 2025-01-31 Donu Arapura , Botong Wang

A product of K\"ahler manifolds also carries a K\"ahler metric. In this short note we would like to study the product of generalized $p-$K\"ahler manifolds, compact or not. The results we get extend the known results (balanced, SKT, sG…

Differential Geometry · Mathematics 2017-02-16 Lucia Alessandrini

Under mild assumptions on a group G, we prove that the class of complete Riemannian n-manifolds of uniformly bounded negative sectional curvatures and with the fundamental groups isomorphic to G breaks into finitely many tangential homotopy…

Differential Geometry · Mathematics 2007-05-23 Igor Belegradek

We study topological obstructions to the existence of a Riemannian metric on manifolds with boundary such that the scalar curvature is non-negative and the boundary is mean convex. We construct many compact manifolds with boundary which…

Differential Geometry · Mathematics 2019-05-22 Ezequiel Barbosa , Franciele Conrado

A notable example due to Heier, Lu, Wong, and Zheng shows that there exist compact complex K\"ahler manifolds with ample canonical line bundle such that the holomorphic sectional curvature is negative semi-definite and vanishes along…

Differential Geometry · Mathematics 2023-11-21 Yongchang Chen , Gordon Heier

We show that a unipotent vector bundle on a non-Kaehler compact complex manifold does not admit a flat holomorphic connection in general. We also construct examples of topologically trivial stable vector bundle on compact Gauduchon manifold…

Differential Geometry · Mathematics 2023-09-11 Indranil Biswas , Carlos Florentino

Main Theorem (3.3): Let $M$ be a compact four-dimensional manifold either with curvature, positive on complex isotropic two-planes, or self-dual of positive scalar curvature. If $\pi_1 (M)$ admits a nontrivial unitary representation, and…

dg-ga · Mathematics 2016-08-31 Alexander G. Reznikov

We formalize the ``metric bundle'' viewpoint by defining, for any smooth $n$--manifold $M$, the open fiberwise cones $\mathcal{G}^{p,q}\subset S^2\Tstar M$ of nondegenerate symmetric bilinear forms with fixed signature $(p,q)$, and we…

Differential Geometry · Mathematics 2025-10-21 Shouvik Datta Choudhury

Given a complex manifold $X$, any K\"ahler class defines an affine bundle over $X$, and any K\"ahler form in the given class defines a totally real embedding of $X$ into this affine bundle. We formulate conditions under which the affine…

Complex Variables · Mathematics 2020-06-18 Daniel Greb , Michael Lennox Wong

Let $M$ be an orientable connected $n$-dimensional manifold with $n\in\{6,7\}$ and let $Y\subset M$ be a two-sided closed connected incompressible hypersurface which does not admit a metric of positive scalar curvature (abbreviated by psc).…

Differential Geometry · Mathematics 2023-07-03 Simone Cecchini , Daniel Räde , Rudolf Zeidler

Up to finite \'etale cover, any smooth complex projective variety $X$ with nef anti-canonical bundle is a holomorphic fibre bundle over a $K$-trivial variety with locally constant transition functions. We show that this result is optimal by…

Algebraic Geometry · Mathematics 2025-03-26 Niklas Müller

We prove vanishing results for the generalized Miller-Morita-Mumford classes of some smooth bundles whose fiber is a closed manifold that supports a nonpositively curved Riemannian metric. We also find, under some extra conditions, that the…

Algebraic Topology · Mathematics 2017-05-17 Mauricio Bustamante , F. Thomas Farrell , Yi Jiang

Given any integer $n\geq 2$, we construct a compact K\"ahler-Einstein manifold of dimension n of negative sectional curvature which is not covered by the ball.

Differential Geometry · Mathematics 2026-05-05 Henri Guenancia , Ursula Hamenstädt
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