Sieve methods and class-number problems III.
Simple proofs of the Siegel-Tatuzawa and Brauer-Siegel theorems
We give a simple proof of the Siegel-Tatuzawa theorem according to which the residues at s = 1 of the Dedekind zeta functions of quadratic number fields are effectively not too small, with at most one exceptional quadratic field. We then give a simple proof of the Brauer-Siegel theorem for normal number fields which gives the asymptotics for the logarithm of the product of the class number and the regulator of number fields.
Small points on a multiplicative group and class number problem
Let be an algebraic subvariety of a torus and denote by the complement in of the Zariski closure of the set of torsion points of . By a theorem of Zhang, is discrete for the metric induced by the normalized height . We describe some quantitative versions of this result, close to the conjectural bounds, and we discuss some applications to study of the class group of some number fields.
Solution du problème du dixième discriminant
Solution of small class number problems for cyclotomic fields
Solution of the Classs Number Two Problem for Cyclotomic Fields.
Some Analytic Estimates of Class Numbers and Discriminants.
Some bases of the Stickelberger ideal
Some generalizations of the Sₙ sequence of Shanks
Some new maps and ideals in classical Iwasawa theory with applications
We introduce a new ideal of the p-adic Galois group-ring associated to a real abelian field and a related ideal for imaginary abelian fields, Both result from an equivariant, Kummer-type pairing applied to Stark units in a -tower of abelian fields, and is linked by explicit reciprocity to a third ideal studied more generally in [D. Solomon, Acta Arith. 143 (2010)]. This leads to a new and unifying framework for the Iwasawa theory of such fields including a real analogue of Stickelberger’s Theorem,...
Some quartic number fields containing an imaginary quadratic subfield
Let ε be a quartic algebraic unit. We give necessary and sufficient conditions for (i) the quartic number field K = ℚ(ε) to contain an imaginary quadratic subfield, and (ii) for the ring of algebraic integers of K to be equal to ℤ[ε]. We also prove that the class number of such K's goes to infinity effectively with the discriminant of K.
Some results from the tables of irregularity index of a prime
Spacing of zeros of Hecke L-functions and the class number problem
Stabilization in non-abelian Iwasawa theory
Let K/k be a ℤₚ-extension of a number field k, and denote by kₙ its layers. We prove some stabilization properties for the orders and the p-ranks of the higher Iwasawa modules arising from the lower central series of the Galois group of the maximal unramified pro-p-extension of K (resp. of the kₙ).
Stark units and Kolyvagin's "Euler systems".
Steinitz classes and discriminant counting
Steinitz classes of cyclic extensions of prime degree.
Steinitz classes of some abelian and nonabelian extensions of even degree
The Steinitz class of a number field extension is an ideal class in the ring of integers of , which, together with the degree of the extension determines the -module structure of . We denote by the set of classes which are Steinitz classes of a tamely ramified -extension of . We will say that those classes are realizable for the group ; 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...
Stickelberger ideal and signature of circular units.
Stickelberger ideal of a compositum of a real bicyclic field and a quadratic imaginary field