【摘要】 本文讨论了二次曲面的径平面、中心、主方向及主平面等几何性质在洛仑兹变换下的情况，结果表明，有的在变换前后保持不变，有的则有变化．更多还原

【Abstract】 This paper discusses Lorents transformation of guadric geometrical characteristics such as the radial plane, the centre, the main direction and the main plane etc. The results show that some of them remain unchanged and some are changeable.更多还原