nLab quadric

Idea

A quadric is an algebraic variety defined as the zero locus of a quadratic function.

Examples

• The quadrics in the Euclidean plane are the conic sections.

• Klein quadric

References

Textbook account:

• Igor R. Shafarevich, Alexey O. Remizov: §11 in: Linear Algebra and Geometry (2012) [doi:10.1007/978-3-642-30994-6, MAA-review]

See also:

• Wikipedia, Quadric, Quadric (Projective geometry))