The absolute Galois group of a pseudo real closed field
The Boolean space of higher level orderings
Let K be an ordered field. The set X(K) of its orderings can be topologized to make it a Boolean space. Moreover, it has been shown by Craven that for any Boolean space Y there exists a field K such that X(K) is homeomorphic to Y. Becker's higher level ordering is a generalization of the usual concept of ordering. In a similar way to the case of ordinary orderings one can define a topology on the space of orderings of fixed exact level. We show that it need not be Boolean. However, our main theorem...
The Galois Cohomology of Pythagorean Fields.
The intersection theorem for orderings of higher level in rings.
The Noether-Lefschetz theorem and sums of 4 squares in the rational function field
The Pythagoras number of some affine algebras and local algebras.
The reduced Wittring
The Undecidability of Pseudo Real Closed Fields.
Theoreme de Pfister pour les varietes et anneaux de Witt reduits.
Trace forms of central simple algebras.
Two theorems on regularly r-closed fields.