English

A hermitian analogue of the Broecker-Prestel theorem

Rings and Algebras 2012-02-07 v3

Abstract

The Broecker-Prestel local-global principle characterizes weak isotropy of quadratic forms over a formally real field in terms of weak isotropy over the henselizations and isotropy over the real closures of that field. A hermitian analogue of this principle is presented for algebras of index at most two. An improved result is also presented for algebras with a decomposable involution, algebras of pythagorean index at most two, and algebras over SAP and ED fields.

Keywords

Cite

@article{arxiv.0707.3754,
  title  = {A hermitian analogue of the Broecker-Prestel theorem},
  author = {Vincent Astier and Thomas Unger},
  journal= {arXiv preprint arXiv:0707.3754},
  year   = {2012}
}

Comments

Final pre-publication version