Genera in normal extensions

SPINOR GENERA UNDER Zp-EXTENSIONS

Let L be a quadratic lattice over a number field F . We lift the lattice L along a Zp-extension of F and investigate the growth of the number of spinor genera in the genus of L. Let Ln be the lattice obtained from L by extending scalars to the n-th layer of the Zp-extension. We show that, under various conditions on L and F , the number of spinor genera in the genus of Ln is 2 +O(1) where η is ...

NORMAL FIELD EXTENSIONS Kjk AND

Throughout the paper Kjk is a field extension and p is the exponent characteristic. In this paper I introduce the notion of .K/fc-bialgebra (coalgebra over K and algebra over k) and describe a theory of finite dimensional normal field extensions Kjk based on a ^-measuring A /̂A:-bialgebra H(Kjk) (see 1.2, 1.6 and 1.10). This approach to studying Kjk was inspired by my conviction that a successfu...

Large Normal Extensions of Hilbertian Fields

Let K be a countable separably Hilbertian field. Denote the absolute Galois group of K by G(K). For each σ ∈ (σ1, . . . , σe) ∈ G(K) let Ks[σ] be the maximal Galois extension of K which is fixed by σ1, . . . , σe. We prove that for almost all σ ∈ G(K) (in the sense of the Haar measure) the field Ks[σ] is PAC and its absolute Galois group is isomorphic to F̂ω. Mathematische Zeitschrift 224 (1997)...

conjugacy separability of certain hnn extensions with normal associated subgroups

in this paper, we will give necessary and sufficient conditions for certain hnnextensions of subgroup separable groups with normal associated subgroup to be conjugacyseparable. in fact, we will show that these hnn extensions are conjugacy separable if and onlyif the normalizer of one of its associated subgroup is conjugacy separable.

Morphisms of Mislin Genera Induced by Finite Normal Subgroups