On reciprocity equivalence of quadratic number fields
On Some Hasse Principles over Formally Real Fields.
On the Cohomological Characterization of Real Free Pro-2-Group.
On the cokernel of the Witt decomposition map
Let be a Dedekind domain with field of fractions and a finite group. We show that, if is a ring of -adic integers, then the Witt decomposition map between the Grothendieck-Witt group of bilinear -modules and the one of finite bilinear -modules is surjective. For number fields is also surjective, if is a nilpotent group of odd order, but there are counterexamples for groups of even order.
On the group .
On the Hasse principle for Witt groups.
On the ...-invariant for quadratics forms and the linkage of cyclic algebras.
On the Milnor exact sequence for global function fields
On the nonexcellence of field extensions .
On the representation of rational functions as sums of squares
On the Witt ring of a relative projective line
On the Witt rings of function fields of quasihomogeneous varieties
On trace forms of étale algebras and field extensions.
On vanishing theorems for trace forms
On Witt rings of function fields of real analytic surfaces and curves.
Let V be a paracompact connected real analytic manifold of dimension 1 or 2, i.e. a smooth curve or surface. We consider it as a subset of some complex analytic manifold VC of the same dimension. Moreover by a prime divisor of V we shall mean the irreducible germ along V of a codimension one subvariety of VC which is an invariant of the complex conjugation. This notion is independent of the choice of the complexification VC. In the one-dimensional case prime divisors are just points, in the two-dimensional...
Partially defined cocycles and the Maslov index for a local ring
In this paper we study some aspects of the cohomology of groups and we construct a central extension of the symplectic group .
Pfaffians, central simple algebras and similtudes.
Picard groups of Witt rings.
Pro-2-Demuskin groups of rank ...0 as Galois groups of maximal 2-extensions of fields.
Quadratic field extensions and residue homomorphisms of Witt rings