Simple birational extensions of two dimensional affine rational domains
Soient un corps commutatif et un idéal de l’anneau des polynômes (éventuellement ). Nous prouvons une conjecture de C. Berenstein - A. Yger qui affirme que pour tout polynôme , élément de la clôture intégrale de l’idéal , on a une représentationoù .
We are concerned with solving polynomial equations over rings. More precisely, given a commutative domain A with 1 and a polynomial equation antn + ...+ a0 = 0 with coefficients ai in A, our problem is to find its roots in A.We show that when A = B[x] is a polynomial ring, our problem can be reduced to solving a finite sequence of polynomial equations over B. As an application of this reduction, we obtain a finite algorithm for solving a polynomial equation over A when A is F[x1, ..., xN] or F(x1,...
We consider Stanley-Reisner rings where is the edge ideal associated to some particular classes of hypergraphs. For instance, we consider hypergraphs that are natural generalizations of graphs that are lines and cycles, and for these we compute the Betti numbers. We also generalize some known results about chordal graphs and study a weak form of shellability.
On the ring of polynomials in n variables over a field special isomorphisms ’s of into are defined which preserve the greatest common divisor of two polynomials. The ring is extended to the ring and the ring of generalized polynomials in such a way that the exponents of the variables are non-negative rational numbers and rational numbers, respectively. The isomorphisms ’s are extended to automorphisms ’s of the ring . Using the property that the isomorphisms ’s preserve GCD it...
We define nice partitions of the multicomplex associated with a Stanley ideal. As the main result we show that if the monomial ideal is a CM Stanley ideal, then is a Stanley ideal as well, where is the polarization of .
In this note we study some algebraic properties of Borel Ideals in the ring of polynomials over an effective field of characteristic zero by using a suitable partial order relation defined on the set of terms of each degree. In particular, in the three variable case, we characterize all the 0-dimensional Borel ideals corresponding to an admissible -vector and their minimal free resolutions.
Résumé. Soit f un polynôme à deux indéterminées. On appelle nombre de Łojasiewicz à l'infini de f le nombre de Łojasiewicz à l'infini de son application gradient. Dans cet article nous montrons tout d'abord que l'on peut calculer le nombre de Łojasiewicz d'un polynôme à partir des diagrammes de Eisenbud et Neumann de toutes les courbes f(x,y) = t. Ensuite nous montrons que l'on peut définir un nombre de Łojasiewicz intrinsèque en prenant le maximum des nombres de Łojasiewicz de f ∘ ϕ si f est bon...