Clebsch对角立方[Clebsch Diagonal Cubic] - 达人(其实～我是卧底，来自外星)

2005/02/01 | Clebsch对角立方[Clebsch Diagonal Cubic]
类别(∑〖数学〗) | 评论(0) | 阅读(28) | 发表于 13:38: A cubic algebraic surface given by the equation
(1)

with the added constraint
(2)

The implicit equation obtained by taking the plane at infinity as is

[(3)

(Hunt, Nordstrand), illustrated above.

On Clebsch's diagonal surface, all 27 of the complex lines (Solomon's seal lines) present on a general smooth cubic surface are real. In addition, there are 10 points on the surface where 3 of the 27 lines meet. These points are called Eckardt points (Fischer 1986, Hunt), and the Clebsch diagonal surface is the unique cubic surface containing 10 such points (Hunt).
If one of the variables describing Clebsch's diagonal surface is dropped, leaving the equations
(4)

(5)

the equations degenerate into two intersecting planes given by the equation
(6); 0