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Nets of conics

Published online by Cambridge University Press:  24 October 2008

C. T. C. Wall
Affiliation:
University of Liverpool

Extract

Segre's classification of pencils of quadrics is well known, and appears in standard texts such as (1), (2). By contrast, other linear systems of quadrics do not lend them-selves to a similar exhaustive treatment. Here we discuss the simplest case, that of nets of conics. The result is intrinsically interesting, and involves some pleasant geometry. As well as deriving a list of types, and enumerating their properties, we study the elementary geometrical properties of the partition of the space Ω of nets into equivalence classes (or strata). We work over the field ℝ of real numbers, after performing preliminary calculations over ℂ.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1977

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References

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