ALGEBRAIC COMBINATORICS

no. 5
Twisted quadrics and α-flocks
Johnson, Norman L.1
1 University of Iowa 750 E. Foster Rd. #306 Iowa City IA 52245
Algebraic Combinatorics, Volume 5 (2022) no. 5, pp. 803-826.

In this article, we provide a general study of what we call twisted quadrics and consider flocks of the variant of α-conics and α-hyperbolic quadrics. We extend the notion of the Klein quadric to what we call an α-Klein quadric. Blended kernel translation planes are defined and analysed when considering α-conical flocks and α-twisted hyperbolic flocks.

The Thas–Walker constructions of conical flocks and flocks of hyperbolic quadrics are extended to their α-analogues. Using the idea that any derivable net can be embedded into a 3-dimensional projective space over a skewfield, allows us to formulate what might be called a projective version of work previously given in an algebraic framework. The theory of deficiency one flocks is extended to both α-conical flocks and α-twisted hyperbolic flocks. j-planes are used to construct two infinite classes of finite α-hyperbolic flocks.

Received:
Revised:
Accepted:
Published online:
DOI: 10.5802/alco.216
Classification: 51E20, 51E14
Keywords: twisted hyperbolic flocks, Klein quadric, j-planes, quasifibrations, T-copies, quaternion division rings
Johnson, Norman L. 1

1 University of Iowa 750 E. Foster Rd. #306 Iowa City IA 52245
License: CC-BY 4.0
Copyrights: The authors retain unrestricted copyrights and publishing rights 
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Johnson, Norman L. Twisted quadrics and $\alpha $-flocks. Algebraic Combinatorics, Volume 5 (2022) no. 5, pp. 803-826. doi : 10.5802/alco.216. https://alco.centre-mersenne.org/articles/10.5802/alco.216/

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