Page 1 Next

Displaying 1 – 20 of 27

Showing per page

Some remarks on Hilbert-Speiser and Leopoldt fields of given type

James E. Carter (2007)

Colloquium Mathematicae

Let p be a rational prime, G a group of order p, and K a number field containing a primitive pth root of unity. We show that every tamely ramified Galois extension of K with Galois group isomorphic to G has a normal integral basis if and only if for every Galois extension L/K with Galois group isomorphic to G, the ring of integers O L in L is free as a module over the associated order L / K . We also give examples, some of which show that this result can still hold without the assumption that K contains...

Steinitz classes of some abelian and nonabelian extensions of even degree

Alessandro Cobbe (2010)

Journal de Théorie des Nombres de Bordeaux

The Steinitz class of a number field extension K / k is an ideal class in the ring of integers 𝒪 k of k , which, together with the degree [ K : k ] of the extension determines the 𝒪 k -module structure of 𝒪 K . We denote by R t ( k , G ) the set of classes which are Steinitz classes of a tamely ramified G -extension of k . We will say that those classes are realizable for the group G ; it is conjectured that the set of realizable classes is always a group.In this paper we will develop some of the ideas contained in [7] to obtain some...

Structure galoisienne des anneaux d'entiers d'extensions sauvagement ramifiées. II

Philippe Cassou-Noguès, Jacques Queyrut (1982)

Annales de l'institut Fourier

Soient G le groupe de Galois d’une extension galoisienne finie, N , d’un corps de nombres K et S un ensemble de places de Q , contenant les places de K sauvagement ramifiées dans N . Nous démontrons, dans de nombreux cas particuliers, une conjecture faite par J. Queyrut dans un article précédent : l’ordre de la classe de l’anneau des entiers de N , dans le sous-groupe de torsion du groupe de Grothendieck des Z [ G ] -module localement libres en dehors de S , est égal à 1 ou 2, selon le signe des constantes...

Currently displaying 1 – 20 of 27

Page 1 Next