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On quadrics through five real points

Published online by Cambridge University Press:  24 October 2008

R. H. F. Denniston
R. H. F. Denniston
Affiliation:
University of Leicester
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Extract

Let Q1,…, Q5 be five fixed points (no four coplanar) of the real projective space S3: let s be a variable quadric surface through these points. The set of all such quadrics can be represented by the points of a real S4, in which there is a quartic primal that represents cones. The geometry of this threefold is well known in the complex case, but has hardly been considered at all in the real case: and one object of the present paper is to describe the real threefold and determine its homology groups.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 63 , Issue 2 , April 1967 , pp. 369 - 388
Copyright
Copyright © Cambridge Philosophical Society 1967

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References

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