In this paper, we establish a differential equation about scalar curvature of conformally flat K-contact manifolds, and prove that a conformally symmetric K-contact manifold is a Riemann manifold with constant curvatu...In this paper, we establish a differential equation about scalar curvature of conformally flat K-contact manifolds, and prove that a conformally symmetric K-contact manifold is a Riemann manifold with constant curvature 1. At the same time, the results on Sasaki manifolds which are given by Miyazaawa and Yamagushi are generalized to K-contact manifolds.展开更多
设x:M→An+1是由定义在凸域ΩAn上的某局部严格凸函数xn+1=f(x1,...,xn)给出的超曲面.考虑Hessian度量 g =∑2fxixjdxidxj.若(M,g)是具有非负李奇曲率的紧致Hessian流形且仿射Khler-Scalar曲率为零,作者证明了如果Δρ≤nρ2...设x:M→An+1是由定义在凸域ΩAn上的某局部严格凸函数xn+1=f(x1,...,xn)给出的超曲面.考虑Hessian度量 g =∑2fxixjdxidxj.若(M,g)是具有非负李奇曲率的紧致Hessian流形且仿射Khler-Scalar曲率为零,作者证明了如果Δρ≤nρ2,则函数f一定是二次多项式,其中ρ=[det(fij)]-1n+2.展开更多
文摘In this paper, we establish a differential equation about scalar curvature of conformally flat K-contact manifolds, and prove that a conformally symmetric K-contact manifold is a Riemann manifold with constant curvature 1. At the same time, the results on Sasaki manifolds which are given by Miyazaawa and Yamagushi are generalized to K-contact manifolds.
文摘设x:M→An+1是由定义在凸域ΩAn上的某局部严格凸函数xn+1=f(x1,...,xn)给出的超曲面.考虑Hessian度量 g =∑2fxixjdxidxj.若(M,g)是具有非负李奇曲率的紧致Hessian流形且仿射Khler-Scalar曲率为零,作者证明了如果Δρ≤nρ2,则函数f一定是二次多项式,其中ρ=[det(fij)]-1n+2.
