In this paper we prove that tile set of Riemannian manifolds with parallel Ricci curvature, lower bounds for sectional curvature and injectivity radius and a upper bound for volume is coo compact in Gromov-Hausdroff t...In this paper we prove that tile set of Riemannian manifolds with parallel Ricci curvature, lower bounds for sectional curvature and injectivity radius and a upper bound for volume is coo compact in Gromov-Hausdroff topology. As an application we also prove a pinching result which states that a Ricci flat manifold is flat under certain conditions.展开更多
本文研究了迷向表示分为12个不可约子空间的满旗流形SO(8)/T上不变爱因斯坦度量的问题.利用计算机计算满旗流形SO(8)/T爱因斯坦方程组的方法,得到了满旗流形SO(8)/T上有160个不变爱因斯坦度量(up to a scale)的结果,在等距情况下考虑这...本文研究了迷向表示分为12个不可约子空间的满旗流形SO(8)/T上不变爱因斯坦度量的问题.利用计算机计算满旗流形SO(8)/T爱因斯坦方程组的方法,得到了满旗流形SO(8)/T上有160个不变爱因斯坦度量(up to a scale)的结果,在等距情况下考虑这160个不变爱因斯坦度量,其中1个是凯莱爱因斯坦度量,4个是非凯莱爱因斯坦度量.推广了只对迷向表示分为小于等于6个不可约子空间的满旗流形上不变爱因斯坦度量的研究.展开更多
In this paper we investigate the Einstein＇s hyperbolic geometric flow and obtain some interesting exact solutions for this kind of flow. Many interesting properties of these exact solutions have also been analyzed an...In this paper we investigate the Einstein＇s hyperbolic geometric flow and obtain some interesting exact solutions for this kind of flow. Many interesting properties of these exact solutions have also been analyzed and we believe that these properties of Einstein＇s hyperbolic geometric flow are very helpful to understanding the Einstein equations and the hyperbolic geometric flow.展开更多
基金Supported by National Natural Science Foundation of China (19971081)
文摘In this paper we prove that tile set of Riemannian manifolds with parallel Ricci curvature, lower bounds for sectional curvature and injectivity radius and a upper bound for volume is coo compact in Gromov-Hausdroff topology. As an application we also prove a pinching result which states that a Ricci flat manifold is flat under certain conditions.
基金Supported by the National Nature Science Foundation of China(11171245)RFDP(201001811100071)+1 种基金Scientific Research Fund of Sichuan Provincial Education Department(11ZA261,12ZB294)Sichuan University of Science and Engineering(2011KY07,2012PY17,2012KY06)
基金Supported by Sichuan University of Science and Engineering grant(2012PY17)Sichuan Province University Key Laboratory of Bridge Non-Destruction Detecting and Engineering Computing grant(2014QZJ03)Partially Supported by Scientific Research Fund of Sichuan Province Education Department Grant(15SB0122)
文摘本文研究了迷向表示分为12个不可约子空间的满旗流形SO(8)/T上不变爱因斯坦度量的问题.利用计算机计算满旗流形SO(8)/T爱因斯坦方程组的方法,得到了满旗流形SO(8)/T上有160个不变爱因斯坦度量(up to a scale)的结果,在等距情况下考虑这160个不变爱因斯坦度量,其中1个是凯莱爱因斯坦度量,4个是非凯莱爱因斯坦度量.推广了只对迷向表示分为小于等于6个不可约子空间的满旗流形上不变爱因斯坦度量的研究.
基金The project supported in part by the National Natural Science Foundation of China under Grant No. 10671124 and the Program for New Century Excellent Talents in University of China under Grant No. NCET-05-0390 Acknowledgments The author would like to thank the Center of Mathematical Sciences at Zhejiang University for the great support and hospitality and the referee for pertinent comments and valuable suggestions.
文摘In this paper we investigate the Einstein＇s hyperbolic geometric flow and obtain some interesting exact solutions for this kind of flow. Many interesting properties of these exact solutions have also been analyzed and we believe that these properties of Einstein＇s hyperbolic geometric flow are very helpful to understanding the Einstein equations and the hyperbolic geometric flow.
