M.-A. Knus, J.-P. Tignol: Quartic Exercises

knus@math.ethz.ch, tignol@math.ucl.ac.be

Submission: 2003, Mar 5

A correspondence between quartic etale algebras over a field and quadratic etale extensions of cubic etale algebras is set up and investigated. The basic constructions are laid out in general for sets with a profinite group action and for torsors, and translated in terms of etale algebras and Galois algebras. In the final section, a parametrization of cyclic quartic algebras is given.

2000 Mathematics Subject Classification: 12F10, 12G05

Keywords and Phrases: etale algebras, Galois cohomology

Full text: dvi.gz 93 k, dvi 259 k, ps.gz 426 k, pdf.gz 390 k, pdf 436 k.


Server Home Page