Spacelike Framed Curves with Lightlike Components and Singularities of Their Evolutes and Focal Surfaces in Minkowski 3-space  

作　　者：Peng Cheng LI Dong He PEI Xin ZHAO 

机构地区：[1]School of Mathematics and Statistics,Northeast Normal University,Changchun 130024,P.R.China [2]Department of Mathematics,Harbin Institute of Technology,Weihai 264209,P.R.China [3]School of Mathematics and Statistics,Qingdao University,Qingdao 266071,P.R.China

出　　处：《Acta Mathematica Sinica,English Series》2024年第6期1521-1532,共12页数学学报（英文版）

基　　金：Supported by National Natural Science Foundation of China(Grant No.11671070)。

摘　　要：In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski 3-space.It is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike components.Meanwhile,we show a new geometric invariant to characterise singularities of the focal surface.Then,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关 键 词：Evolutes focal surfaces spacelike framed curves SINGULARITIES 

分 类 号：O186.11[理学—数学]