Results 31 to 40 of about 1,771,776 (376)
On projective manifolds with semi-positive holomorphic sectional curvature [PDF]
American Journal of Mathematics, 2018 :We establish structure theorems for a smooth projective variety $X$ with semi-positive holomorphic sectional curvature. We first prove that $X$ is rationally connected if $X$ has no truly flat tangent vectors at some point (which is satisfied when the ...
Shin-ichi Matsumura
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Mathematics, 2023 In this paper, the authors review and survey some results published since 2020 about (complete) monotonicity, inequalities, and their necessary and sufficient conditions for several newly introduced functions involving polygamma functions and originating
Feng Qi, Ravi Prakash Agarwal
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On the image of MRC fibrations of projective manifolds with semi-positive holomorphic sectional curvature [PDF]
Pure and Applied Mathematics Quarterly, 2018 In this paper, we pose several conjectures on structures and images of maximal rationally connected fibrations of smooth projective varieties admitting semi-positive holomorphic sectional curvature.
Shin-ichi Matsumura
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Geometric inequalities for hypersurfaces with nonnegative sectional curvature in hyperbolic space [PDF]
Calculus of Variations and Partial Differential Equations, 2018 In this article, we will use inverse mean curvature flow to establish an optimal Sobolev-type inequality for hypersurfaces $$\Sigma $$Σ with nonnegative sectional curvature in $$\mathbb {H}^n$$Hn.
Yingxiang Hu, Haizhong Li
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Quasiprojective manifolds with negative holomorphic sectional curvature [PDF]
Duke mathematical journal, 2018 Let $(M,\omega)$ be a compact K\"ahler manifold with negative holomorphic sectional curvature. It was proved by Wu-Yau and Tosatti-Yang that $M$ is necessarily projective and has ample canonical bundle.
Henri Guenancia
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Pointwise orthogonal splitting of the space of TT-tensors
Дифференциальная геометрия многообразий фигур, 2023 In the present paper we consider pointwise orthogonal splitting of the space of well-known TT-tensors on Riemannian manifolds. Tensors of the first subspace belong to the kernel of the Bourguignon Laplacian, and the tensors of the second subspace ...
S. E. Stepanov, I. I. Tsyganok
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Quasi-negative holomorphic sectional curvature and positivity of the canonical bundle [PDF]
Journal of differential geometry, 2016 We show that if a compact complex manifold admits a K\"ahler metric whose holomorphic sectional curvature is everywhere non positive and strictly negative in at least one point, then its canonical bundle is positive.
Simone Diverio, S. Trapani
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On the geometry of sub-Riemannian manifolds equipped with a canonical quarter-symmetric connection
Дифференциальная геометрия многообразий фигур, 2023 In this article, a sub-Riemannian manifold of contact type is understood as a Riemannian manifold equipped with a regular distribution of codimension-one and by a unit structure vector field orthogonal to this distribution. This vector field is called a
S. V. Galaev
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On the Tachibana numbers of closed manifolds with pinched negative sectional curvature
Дифференциальная геометрия многообразий фигур, 2020 Conformal Killing form is a natural generalization of conformal Killing vector field. These forms were extensively studied by many geometricians. These considerations were motivated by existence of various applications for these forms.
S.E. Stepanov, I. I. Tsyganok
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Strongly positive curvature [PDF]
, 2014 We begin a systematic study of a curvature condition (strongly positive curvature) which lies strictly between positive curvature operator and positive sectional curvature, and stems from the work of Thorpe in the 1970s.
Bettiol, Renato G. +1 more
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