Lifting chains of prime ideals to paravaluation rings

Résumé  SoitR ⊂T une extension des anneaux commutatifs et soit {P _α :α ∈I} une cha?ne croissante des idéaux premiers deR (I étant un ensemble totalement ordonné, peut-être infini). Alors il existe un anneau de paravaluationV deT et une cha?ne {Q _α} des idéaux premiers deV de sorte queR ⊂V etQ _α ∩R =P _α pour toutα ∈I. Tout d’abord, on établit le cas spécial dans lequelT est un corps; dans ce cas, on trouve en effet un tel anneau de valuationV deT. Ensuite, l’assertion ci-dessus pour le cas général découle comme conséquence. Dans le cas général, on peut aussi remplacer le mot “paravaluation” avec le mot “valuation” siR est un anneau de Marot etT est son anneau total de fractions.      

Extensions of commutative rings in which trees of prime ideals contract to trees

Résumé  Une extensionA⊂B des anneaux (commutatifs) satisfait à la propriété si tout arbre dans Spec(B) couvre un arbre dans Spec(A). Il est possible qu'une extension entière d'un anneau Noethérien ne satisfait pas à . SiA⊂B soit unei-extension satisfaisante à soit “going-up” soit “going-down”, alorsA⊂B satisfait à . Cependant, une extension d'anneaux satisfaisante à “going-up”, “going-down”, et peut être nonunibranche dans hauteur >1. Un anneau intègreA a le spectre d'un arbre si et seulement siA⊂B satisfait àP pour tout anneau intègreB contenantA (resp., suranneau de BézoutB deA). De plus, si un anneau intègreA n'ait pas de spectre d'un arbre mais soit localement de dimension finie, (par exemple, tout anneau intègre Noethérien de dimension au moins 2), alors il existe un suranneau de BézoutB deA et un arbre saturé dans Spec(B) de sorte que card=4 et l'image de à l'égard de la flèche canonique Spec(B)→Spec(A) est un ensemble saturé tel que card =3 mais n'est pas d'arbre. On donne également des caractérisations associées des classes desi-domaines et des ai-domaines.      

Lifting up an infinite chain of prime ideals to a valuation ring

We prove that for an arbitrary chain of prime ideals in an integral domain, there exists a valuation domain which has a chain of prime ideals lying over .

     

Regularity of prime ideals

Mathematische Zeitschrift - We answer several natural questions which arise from a recent paper of McCullough and Peeva providing counterexamples to the Eisenbud–Goto Regularity Conjecture....     

High order derivations and primary ideals to regular prime ideals

Ohne Zusammenfassung     

Lifting monomial ideals

We show how to lift any monomial ideal J in n variables to a saturated ideal J of the same codimension in n -+ t variables. We show that I has the same graded Betti numbers as J and we show how to obtain the matrices for the resolution of I. The cohornology of l is described. Making general choices for our lifting, we show that l is the ideal of a reduced union of linear varieties with singularities that are "as small as possible" given the cohomological constraints. The case where J is Artinian is the nicest. In the case of curves we obtain stick figures for l, and in the case of points we obtain certain k-configurations which we can describe in a very precise way.     

Estimates for prime ideals

A modification of an old argument due to ?ebi?ev is used to obtain uniform estimates for prime ideals in algebraic number fields.     

Uppers to zero in intersections of prime ideals

Let R be a Noetherian integral domain. The structure of the partially-ordered set of prime ideals of R[z], the polynomial ring in one indeterminate over R, is not fully understood. I demonstrate that if p₁,…,p_n are prime ideals in R[x] with ht(p_i) > 2 and either n = 1 or R is not a Henselian local domain of dimension < 2, then pi D-o-C\pn contains [R] many prime ideals which intersect R at (0). I also show that if R is a Noetherian domain that is not a Henselian local domain and p₁,…,p_n are prime ideals with height > 2 each of which contains a monic polynomial, then their intersection contains [R] many prime ideals meeting R at (0), each containing a monic polynomial.     

The spin of prime ideals

Fixing a nontrivial automorphism of a number field K, we associate to ideals in K an invariant (with values in {0,±1}) which we call the spin and for which the associated L-function does not possess Euler products. We are nevertheless able, using the techniques of bilinear forms, to handle spin value distribution over primes, obtaining stronger results than the analogous ones which follow from the technology of L-functions in its current state. The initial application of our theorem is to the arithmetic statistics of Selmer groups of elliptic curves.     

On rings whose prime ideals are completely prime

We investigate in this paper rings whose proper ideals are 2-primal. We concentrate on the connections between this condition and related concepts to this condition, and several kinds of π-regularities of rings which satisfy this condition. Moreover, we add counterexamples to the situations that occur naturally in the process of this note.     

Tameness of local cohomology of monomial ideals with respect to monomial prime ideals

In this paper we consider the local cohomology of monomial ideals with respect to monomial prime ideals and show that all these local cohomology modules are tame.     

Prime elements from prime ideals

The prime ideal theorem for distributive lattices (PIT) is shown to imply that any complete distributive lattice with a compact unit has a prime element, which is then used to deduce from PIT that (1) every nontrivial ring with unit has a prime ideal, and (2) every Wallman locale is spatial.     

On minimal strongly prime ideals

In this paper we give some characterizations of a ring Rwhose unique maximal nil ideal N _r (R) coincides with the set of all its nilpotent elements N(R) by using its minimal strongly prime ideals.