Singularities Of Null Hypersurfaces Of Pseudo Null Curves In Minkowski 4-Space

This paper mainly studies the singularities of null hypersurfaces of pseudo null curves in Minkowski 4-space.We construct the Frenet type frame and Lorentz distance-squared functions of the pseudo null curve,by using singularity theory and function unfolding theory,we discusse the relationship between singularities of the null hypersurfaces and Lorentz distance-squared functions,given the classification of the null hypersurface singularities.In addition,this paper also gives the geometrical properties of the singularities of such hypersurfaces.