## Innovations in Incidence Geometry

### Projections of quadrics in finite projective spaces of odd characteristic

#### Abstract

The set of points obtained by projecting a quadric from a point off the quadric on a hyperplane has many interesting properties. Hirschfeld and Thas provided a characterization of this set, only by means of its intersection pattern with lines. However, their result only holds when the finite field has even order. Here, we extend their result to finite fields of odd order.

#### Article information

Source
Innov. Incidence Geom., Volume 3, Number 1 (2006), 51-80.

Dates
Received: 31 August 2005
First available in Project Euclid: 28 February 2019

Permanent link to this document
https://projecteuclid.org/euclid.iig/1551323240

Digital Object Identifier
doi:10.2140/iig.2006.3.51

Mathematical Reviews number (MathSciNet)
MR2267606

Zentralblatt MATH identifier
1113.51001

#### Citation

De Clerck, Frank; De Feyter, Nikias. Projections of quadrics in finite projective spaces of odd characteristic. Innov. Incidence Geom. 3 (2006), no. 1, 51--80. doi:10.2140/iig.2006.3.51. https://projecteuclid.org/euclid.iig/1551323240

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