Families of Curves on Surfaces.
Families of Curves with Nodes on K-3 Surfaces.
Families of supersingular abelian surfaces
Felix Klein's paper on real flexes vindicated
In a paper written in 1876 [4], Felix Klein gave a formula relating the number of real flexes of a generic real plane projective curve to the number of real bitangents at non-real points and the degree, which shows in particular that the number of real flexes cannot exceed one third of the total number of flexes. We show that Klein's arguments can be made rigorous using a little of the theory of singularities of maps, justifying in particular his resort to explicit examples.
Filtration par le poids et monodromie entière
Formulae for the singularities at infinity of plane algebraic curves.
Fundamental group of a class of rational cuspidal curves.
Fundamental groups of some special quadric arrangements.
Continuing our work on the fundamental groups of conic-line arrangements (Amram et al., 2003), we obtain presentations of fundamental groups of the complements of three families of quadric arrangements in P2. The first arrangement is a union of n conics, which are tangent to each other at two common points. The second arrangement is composed of n quadrics which are tangent to each other at one common point. The third arrangement is composed of n quadrics, n-1 of them are tangent to the n-th one...