A perturbative method of computing the total travel time of both null and lightlike rays in arbitrary static spherically......

讨论了三维Minkowski空间中Mannheim侣线的曲率与挠率之间的关系,证明了Mannheim侣线的曲率与挠率满足的关系式.......

采用活动标架法,得到de Sitter空间中类时子流形的 Ricci 恒等式和第二基本形式长度平方的Laplacian,并得到de Sitter空间中紧致极......