Décomposition cellulaire de variétés paramétrant des idéaux homogènes de C [[x,y]]. Incidence des cellules - II -.
Décomposition cellulaire de variétés paramétrant des idéaux homogènes de . Incidence des cellules I
El polinomio de Poincaré-Hodge de un producto simétrico de variedades kählerianas compactas.
In this paper we compute the Poincaré-Hodge polynomial of a symmetric product of a compact kähler manifold, following the method used by Macdonald, in the topological case, to compute the Poincaré polynomial of a compact polyhedron, and we give some applications, in particular to the case of curves.
Erratum to : “The finite free extension of artinian -algebras with the strong Lefschetz property” [Rend. Sem. Mat. Univ. Padova 110 (2003), 119–146]
Espace des germes d'arcs réels et série de Poincaré d'un ensemble semi-algébrique
Nous définissons l’espace des germes d’arcs réels tracés sur un ensemble semi-algébrique de , analogue réel de la théorie développée par Denef et Loeser concernant l’espace des germes d’arcs tracés sur une variété algébrique complexe. Puis, reprenant leur méthodes, nous prouvons la rationalité de la série de Poincaré associée à un ensemble semi-algébrique.
Extensions of toric varieties.
Families of reduced zero-dimensional schemes.
A great deal of recent activity has centered on the question of whether, for a given Hilbert function, there can fail to be a unique minimum set of graded Betti numbers, and this is closely related to the question of whether the associated Hilbert scheme is irreducible or not. We give a broad class of Hilbert functions for which we show that there is no minimum, and hence that the associated Hilbert sheme is reducible. Furthermore, we show that the Weak Lefschetz Property holds for the general element...
Fredholm spectrum and growth of cohomology groups
Let T ∈ L(E)ⁿ be a commuting tuple of bounded linear operators on a complex Banach space E and let be the non-essential spectrum of T. We show that, for each connected component M of the manifold of all smooth points of , there is a number p ∈ 0, ..., n such that, for each point z ∈ M, the dimensions of the cohomology groups grow at least like the sequence with d = dim M.
Hilbert functions, Castelnuovo-Mumford regularity and uniform Artin-Rees numbers.
Hilbert functions on Cohen-Macaulay ideals with assigned generators’ degrees
Hilbert series and applications to graded rings.
Hilbert series of the Grassmannian and -Narayana numbers
We compute the Hilbert series of the complex Grassmannian using invariant theoretic methods. This is made possible by showing that the denominator of the -Hilbert series is a Vandermonde-like determinant. We show that the -polynomial of the Grassmannian coincides with the -Narayana polynomial. A simplified formula for the -polynomial of Schubert varieties is given. Finally, we use a generalized hypergeometric Euler transform to find simplified formulae for the -Narayana numbers, i.e. the -polynomial...
Hilbert-Kunz function of monomial ideals and binomial hypersurfaces.
Hilbert-Poincaré series of bigraded algebras
Lo scopo di questo lavoro è la descrizione di alcune nuove tecniche per calcolare serie di Hilbert-Poincaré (HP-serie) di algebre standard, che possono essere viste come sottoalgebre di algebre bigraduate. In particolare mostriamo come calcolare in modo uniforme le HP-serie delle potenze di un idele omogeneo. Mostriamo anche come calcolare le HP-serie di prodotti di Segre e di alcune algebre di Blow-up, che sono di interesse in Geometria Algebrica. Per alcune classi siamo in grado di descrivere...
Homotopy Lie algebras and Poincaré series of algebras with monomial relations.
Ideals with maximal local cohomology modules
Interpretations of the -vector.
Lech-Hironaka Inequalities for Flat couples of local rings.
Linear systems with multiple base points in .
Lower bounds for Betti numbers