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A Family of Unitals in the Hughes Plane

Published online by Cambridge University Press:  20 November 2018

Barbu C. Kestenband*
Affiliation:
New York Institute of Technology, Wheatley Rd., Old Westbury N.Y. 11568, U.S.A.
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We construct a family of unitals in the Hughes plane. We prove that they are not isomorphic with the classical unitals, and in so doing we exhibit a configuration that exists in the latter, but not in the former. This new configurational property of the classical unitals might serve in the future again as an isomorphism test.

A particular instance of our construction has appeared in [11]. But it only concerns itself with the case where the matrix involved is the identity, whereas the present article treats the general case of symmetric matrices over a suitable field. Furthermore, [11] does not answer the isomorphism question. It states that (the English translation is ours) “It remains to be seen whether the unitary designs constructed in this note are isomorphic or not with known designs”.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1990

References

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