Niveau: Supérieur, Doctorat, Bac+8
1GENERALIZED ENRIQUES DIAGRAMS AND CHARACTERISTIC CONES GERARD GONZALEZ-SPRINBERG Abstract. Generalized Enriques diagrams are combinatorial data as- sociated with constellations of infinitely near points and proximity re- lations. Classically they were introduced to deal with linear systems of curves with base conditions. We present a survey on some aspects and new results on this diagrams, examples and applications to relative characteristic cones and Zariski's complete ideal theory. 1. Introduction In [6] (Libro Quarto: “Le singolarita delle curve algebriche”, I. 12 et II. 17), Enriques and Chisini consider systems of plane curves passing, with assigned multiplicities, through an assigned set of points or infinitely near points to a point of the plane. They found that there exist curves with such prescribed multiplicities (with no conditions on the degree of the curves) if and only if some inequalities, on these virtual multiplicities, hold for the given points, the so-called proximity relations. Enriques associates a graph (“schema grafico”) to the constellation of infinitely near points appearing in the desingularisation of a plane curve and equiped this graph with the data of the proximity relations which keep track of the incidence between points and the exceptional divisors obtained by blowing-up precedent points. Du Val also considers these proximities relations (see [5]) and defines the proximity matrix. Some years later Zariski introduces the notion of complete ideals to give a new algebraic setup of the previous geometric theory ([14], [15]), where complete (i.
- cone associated
- intermediate point
- dimensional local
- generalized enriques
- characteristic cones
- dimension than
- minimum dimension
- complete ideals