projective geometry;
de Sitter world;
symplectic algebra;
Klein model;
D O I:
10.1016/j.geomphys.2004.07.008
中图分类号:
O29 [应用数学];
学科分类号:
070104 ;
摘要:
An isomorphism between the Lobachevsky and de Sitter's world geometries with the symplectic geometry and the Lie algebra of binary quadratic forms is used to derive the altitudes concurrence for the Lobachevsky and de Sitter triangles. (c) 2004 Elsevier B.V. All rights reserved.