Ⅲ.几何尽管李羣論是和微分几何密切是相关的,嘉当在微分几何方面的主要工作却不是在比較靠后的阶段才开始的。他在微分几何方面的第一批文章是討論变形問題的。很清楚在那时候他已經有了活动标架方法的主要思想,活动标架方法是他在以后的年月里他自己特別爱好的題目之一,它至今还沒有完全探索清楚。这方法不是新的。它是Darboux,Ribaucour和其他人所成功地运用的活动三面体的方法在任意齐性空間中的推广。即使在最一般的情形下它的某些 III. Geometry Although Lie group theory is closely related to differential geometry, the major work of Jiadang in differential geometry did not begin at a later stage. His first articles on differential geometry were discussing deformation issues. It was clear that he had already had the main idea of ​​the moving frame method at that time. The moving frame method was one of his favorite subjects in his later years. It has not yet been fully explored. This method is not new. It is the promotion of the trihedral method that Darboux, Ribaucour, and others have successfully used in any homogeneous space. Even in the most general case it’s some