engleski

Classification of Quadrics in Double Isotropic Space

This paper gives the classification of second order surfaces in double isotropic space (I_3)^(2)Although quadrics in (I_3)^(2) have been investigated earlier [e.g. 8 or 9], this paper offers a new method based on Linear Algebra. The definition of invariants of a quadric with respect to the group of motions in (I_3)^(2) makes it possible to determine the type of a quadric without reducing its equation to canonical form. For that purpose isometric properties of conics in the isotropic plane and affine properties of quadrics are used.

quadrics; plane isotropic geometry; geometry of the double isotropic space

nije evidentirano