Springer's theorem for tame quadratic forms over Henselian fields
K-Theory and Homology
2010-02-08 v1 Algebraic Geometry
Abstract
A quadratic form over a Henselian-valued field of arbitrary residue characteristic is tame if it becomes hyperbolic over a tamely ramified extension. The Witt group of tame quadratic forms is shown to be canonically isomorphic to the Witt group of graded quadratic forms over the graded ring associated to the filtration defined by the valuation, hence also isomorphic to a direct sum of copies of the Witt group of the residue field indexed by the value group modulo 2.
Cite
@article{arxiv.1002.1153,
title = {Springer's theorem for tame quadratic forms over Henselian fields},
author = {Mohamed Abdou Elomary and Jean-Pierre Tignol},
journal= {arXiv preprint arXiv:1002.1153},
year = {2010}
}