In this paper we introduce the concept of (ε)-almost paracontact manifolds, and in particular, of (ε)-para Sasakian manifolds. Several examples are presented. Some typical identities for curvature tensor and Ricci tensor of (ε)-para Sasakian manifolds are obtained. We prove that if a semi-Riemannian manifold is one of flat, proper recurrent or proper Ricci-recurrent, then it can not admit an (ε...

In this paper, we derive a partial result related to a question of Professor Yau: “Does a simply-connected complete Kähler manifold M with negative sectional curvature admit a bounded non-constant holomorphic function?” Main Theorem. Let M be a simply-connected complete Kähler manifold M with negative sectional curvature ≤ −1 and S∞(M) be the sphere at infinity of M . Then there is an explicit ...

In this work, we obtain a existence criteria for the longtime K\ahler Ricci flow solution. Using result, generalize result by Wu-Yau on of Einstein metric to case with possibly unbounded curvature. Moreover, negative scalar curvture must be unique up scaling.

It is well known that \({\mathbb {C}}H^n\) has the structure of a solvable Lie group with left invariant metric constant holomorphic sectional curvature. In this paper we give full classification all possible Riemannian metrics on group. We prove each those negative scalar curvature, only one them being Einstein (up to isometry and scaling).

We prove that a smooth complex projective threefold with a Kähler metric of negative holomorphic sectional curvature has ample canonical line bundle. In dimensions greater than three, we prove that, under equal assumptions, the nef dimension of the canonical line bundle is maximal. With certain additional assumptions, ampleness is again obtained. The methods used come from both complex differen...

This paper discusses the Norden golden manifold having a constant sectional curvature. First, it is shown that if has real curvature, flat. For this reason, notions of holomorphic-like curvature and bisectional on are investigated, but seen these do not work manifold. shows need for new concept In direction, notion (Norden curvature) proposed, an example given, constant, tensor field expressed ...