English

Some Extensions of Witt's Theorem

Algebraic Geometry 2007-05-29 v1 Representation Theory

Abstract

We extend Witt's theorem to several kinds of simultaneous isometries of subspaces. We determine sufficient and necessary conditions for the extension of an isometry of subspaces ϕ:EE\phi:E\to E' to an isometry ϕV:VV\phi_V:V\to V' that also sends a given subspace to another, or a given self-dual flag to another, or a Witt's decomposition to another and a special self-dual flag to another. We also determine sufficient and necessary conditions for the isometry of generic flags or the simultaneous isometry of (subspace, self-dual flag) pairs.

Keywords

Cite

@article{arxiv.0705.3839,
  title  = {Some Extensions of Witt's Theorem},
  author = {Huajun Huang},
  journal= {arXiv preprint arXiv:0705.3839},
  year   = {2007}
}
R2 v1 2026-06-21T08:32:13.562Z