We describe all Witt invariants and mod 2 cohomological invariants of the functor
as
combinations of fundamental invariants; this is related to the study of operations on
mod 2 Milnor K-theory. We also study behaviour of these invariants with respect to
products, restrictions, similitudes and ramification.
Keywords
cohomological invariants, Witt ring, fundamental ideal,
Pfister forms, Witt invariants