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CHARACTERIZING HERMITIAN VARIETIES IN THREE- AND FOUR-DIMENSIONAL PROJECTIVE SPACES

Published online by Cambridge University Press:  29 October 2018

ANGELA AGUGLIA*
Affiliation:
Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Via Orabona 4, I-70126 Bari, Italy email angela.aguglia@poliba.it

Abstract

We characterize Hermitian cones among the surfaces of degree $q+1$ of $\text{PG}(3,q^{2})$ by their intersection numbers with planes. We then use this result and provide a characterization of nonsingular Hermitian varieties of $\text{PG}(4,q^{2})$ among quasi-Hermitian ones.

Type
Research Article
Copyright
© 2018 Australian Mathematical Publishing Association Inc. 

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Footnotes

The author was supported by the Italian National Group for Algebraic and Geometric Structures and their Applications (GNSAGA–INdAM).

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