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arXiv · 1304.0231

The Betten-Walker spread and Cayley's ruled cubic surface

Hans Havlicek·Rolf Riesinger
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Abstract

We establish that, over certain ground fields, the set of osculating tangents of Cayley's ruled cubic surface gives rise to a (maximal partial) spread which is also a dual (maximal partial) spread. It is precisely the Betten-Walker spreads that allow for this construction. Every infinite Betten-Walker spread is not an algebraic set of lines, but it turns into such a set by adding just one pencil of lines.

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Hans Havlicek, Rolf Riesinger. 2013-03-31. The Betten-Walker spread and Cayley's ruled cubic surface. https://arxiv.org/abs/1304.0231

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