Nets of conics of rank one in PG(2,q), q odd (2003.06275v1)

Abstract: We classify nets of conics in Desarguesian projective planes over finite fields of odd order, namely, two-dimensional linear systems of conics containing a repeated line. Our proof is geometric in the sense that we solve the equivalent problem of classifying the orbits of planes in $\text{PG}(5,q)$ which meet the quadric Veronesean in at least one point, under the action of $\text{PGL}(3,q) \leqslant \text{PGL}(6,q)$ (for $q$ odd). Our results complete a partial classification of nets of conics of rank one obtained by A. H. Wilson in the article "The canonical types of nets of modular conics", American Journal of Mathematics 36 (1914) 187-210.