English

Covariants and the no-name lemma

Representation Theory 2008-06-25 v2 Algebraic Geometry

Abstract

A close connection between the no-name lemma (concerning algebraic groups acting on vector bundles) and the existence of sufficiently many independent rational covariants is pointed out. In particular, this leads to a new natural proof of the no-name lemma. For linearly reductive groups, the approach has a refined variant based on integral covariants. This fits into the usual context of invariant theory, and yields a version of the no-name lemma that has a constructive nature.

Keywords

Cite

@article{arxiv.0803.1327,
  title  = {Covariants and the no-name lemma},
  author = {M. Domokos},
  journal= {arXiv preprint arXiv:0803.1327},
  year   = {2008}
}

Comments

The paper has been completely rewritten, more conclusive results are achieved

R2 v1 2026-06-21T10:20:01.039Z