English

Dynamical method in algebra: Effective Nullstellens\"atze

Algebraic Geometry 2025-05-06 v2 Logic

Abstract

We give a general method for producing various effective Null and Positivstellens\"atze, and getting new Positivstellens\"atze in algebraically closed valued fields and ordered groups. These various effective Nullstellens\"atze produce algebraic identities certifying that some geometric conditions cannot be simultaneously satisfied. We produce also constructive versions of abstract classical results of algebra based on Zorn's lemma in several cases where such constructive version did not exist. For example, the fact that a real field can be totally ordered, or the fact that a field can be embedded in an algebraically closed field. Our results are based on the concepts we develop of dynamical proofs and simultaneous collapse.

Keywords

Cite

@article{arxiv.1701.05794,
  title  = {Dynamical method in algebra: Effective Nullstellens\"atze},
  author = {Michel Coste and Henri Lombardi and Marie-Françoise Roy},
  journal= {arXiv preprint arXiv:1701.05794},
  year   = {2025}
}
R2 v1 2026-06-22T17:55:12.583Z