English

A new discriminant algebra construction

Commutative Algebra 2016-12-07 v3 Algebraic Geometry Number Theory

Abstract

A discriminant algebra operation sends a commutative ring RR and an RR-algebra AA of rank nn to an RR-algebra ΔA/R\Delta_{A/R} of rank 22 with the same discriminant bilinear form. Constructions of discriminant algebra operations have been put forward by Rost, Deligne, and Loos. We present a simpler and more explicit construction that does not break down into cases based on the parity of nn. We then prove properties of this construction, and compute some examples explicitly.

Keywords

Cite

@article{arxiv.1503.05318,
  title  = {A new discriminant algebra construction},
  author = {Owen Biesel and Alberto Gioia},
  journal= {arXiv preprint arXiv:1503.05318},
  year   = {2016}
}

Comments

Updated to journal version

R2 v1 2026-06-22T08:55:55.216Z