Smooth curves on a cone which pass through its vertex.
Some defective secant varieties to osculating varieties of Veronese surfaces.
We consider the k-osculating varietiesOk,d to the Veronese d?uple embeddings of P2. By studying the Hilbert function of certain zero-dimensional schemes Y ⊂ P2, we find the dimension of Osk,d, the (s?1)th secant varieties of Ok,d, for 3 ≤ s ≤ 6 and s = 9, and we determine whether those secant varieties are defective or not.
Sur une classe particulière de surfaces réglées
Sur une nouvelle méthode pour l'étude des courbes tracées sur les surfaces algébriques
Symétries des surfaces rationnelles génériques.