An investigation of bounds for the regulator of quadratic fields.
The relative class number of a real quadratic field K = ℚ (√m) of discriminant d is defined to be the ratio of the class numbers of and , where denotes the ring of integers of K and is the order of conductor f given by . R. Mollin has shown recently that almost all real quadratic fields have relative class number 1 for some conductor. In this paper we give a characterization of real quadratic fields with relative class number 1 through an elementary approach considering the cases when...
Fix an element in a quadratic field . Define as the set of rational primes , for which has maximal order modulo . Under the assumption of the generalized Riemann hypothesis, we show that has a density. Moreover, we give necessary and sufficient conditions for the density of to be positive.
Let K = Q(ζp) and let hp be its class number. Kummer showed that p divides hp if and only if p divides the numerator of some Bernoulli number. In this expository note we discuss the generalizations of this type of criterion to totally real fields and quadratic imaginary fields.
For any number field with non-elementary -class group , , the punctured capitulation type of in its unramified cyclic cubic extensions , , is an orbit under the action of . By means of Artin’s reciprocity law, the arithmetical invariant is translated to the punctured transfer kernel type of the automorphism group of the second Hilbert -class field of . A classification of finite -groups with low order and bicyclic commutator quotient , , according to the algebraic invariant...
Dans cette note nous décrivons différentes méthodes utilisées en pratique pour calculer le nombre de classes d'un corps quadratique imaginaire ou réel ainsi que pour calculer le régulateur d'un corps quadratique réel. En particulier nous décrivons l'infrastructure de Shanks ainsi que la méthode sous-exponentielle de McCurley.
For any integer , we provide a parametric family of biquadratic fields with class groups having -rank at least 2. Moreover, in some cases, the -rank is bigger than 4.