S. Rottey

activity

20122015

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3 papers · 1 filter

math.CO2015

A geometric characterisation of Desarguesian spreads

Sara Rottey, John Sheekey

We provide a characterisation of $(n - 1)$ -spreads in $PG (r n - 1, q)$ that have $r$ normal elements in general position. In the same way, we obtain a geometric characterisation…

math.CO2015

Unitals with many Baer secants through a fixed point

Sara Rottey, Geertrui Van de Voorde

We show that a unital $U$ in $PG (2, q^{2})$ containing a point $P$ , such that at least $q^{2} - ε$ of the secant lines through $P$ intersect $U$ in a Baer subline, is an ovoidal…

math.CO2015

Characterisations of elementary pseudo-caps and good eggs

Sara Rottey, Geertrui Van de Voorde

In this note, we use the theory of Desarguesian spreads to investigate good eggs. Thas showed that an egg in $PG (4 n - 1, q)$ , $q$ odd, with two good elements is elementary.…