English

$\mathbb{Z}^2$-algebras as noncommutative blow-ups

Algebraic Geometry 2017-08-01 v2

Abstract

The goal of this note is to first prove that for a well behaved Z2\mathbb{Z}^2-algebra RR, the category QGr(R):=Gr(R)/Tors(R)QGr(R) := Gr(R)/Tors(R) is equivalent to QGr(RΔ)QGr(R_\Delta) where RΔR_\Delta is a diagonal-like sub-Z\mathbb{Z}-algebra of RR. Afterwards we use this result to prove that the Z2\mathbb{Z}^2-algebras as introduced in [ArXiV:1607.08383] are QGr-equivalent to a diagonal-like sub-Z\mathbb{Z}-algebra which is a simultaneous noncommutative blow-up of a quadratic and a cubic Sklyanin algebra. As such we link the noncommutative birational transformation and the associated Z2\mathbb{Z}^2-algebras as appearing in the work of Van den Bergh and Presotto with the noncommutative blowups appearing in the work of Rogalski, Sierra and Stafford.

Keywords

Cite

@article{arxiv.1701.00413,
  title  = {$\mathbb{Z}^2$-algebras as noncommutative blow-ups},
  author = {Dennis Presotto},
  journal= {arXiv preprint arXiv:1701.00413},
  year   = {2017}
}

Comments

20 pages. New in version 2: improved definition for diagonal-like subalgebras + included reference to arXiv:1607.03608 which contains related results

R2 v1 2026-06-22T17:39:14.694Z