Algebraic Number Fields Embedded in Qp

Algebraic number fields

By an algebraic number field we mean a subfield of the algebraic numbers, or an isomorphic copy of such a field. Here we consider questions related to the complexity of determining isomorphism between algebraic number fields. We characterize the algebraic number fields with computable copies. For computable algebraic number fields, we give the complexity of the index sets. We show that the isom...

Normal Algebraic Number Fields.

Introduction. In this paper we present a detailed account of the results recently published in the Proceedings of the National Academy of Sciences [29 Our theory is an attempt to generalize the results of the classical class field theory to arbitrary normal fields. In the last analysis, the theory of cyclic extensions Z of an algebraic number field k can be described in terms of cyclic algebras...

Isomorphisms of Algebraic Number Fields

Let Q(α) and Q(β) be algebraic number fields. We describe a new method to find (if they exist) all isomorphisms, Q(β) → Q(α). The algorithm is particularly efficient if there is only one isomorphism.

Codes from Algebraic Number Fields

INTRODUCTION The geometry of numbers, coding theory, the Riemann hypothesis the list of key words for this lecture can be read äs a partial history of the Stichting Mathematisch Centrum. The lecture itself attempts to reflect the spirit of the SMC by displaying a new connection between these subjects. Using ideas from the geometry of numbers one can construct a class of codes from algebraic num...

Sum-product Theorems in Algebraic Number Fields