Abstract—We show that a quotient of a non-trivial Severi–Brauer surface S over arbitrary field \(\Bbbk \) of characteristic 0 by a finite group \(G \subset {\text{Aut}}(S)\) is \(\Bbbk \)-rational if and only if |G| is divisible by 3. Otherwise, the quotient is birationally equivalent to S.
Similar content being viewed by others
REFERENCES
J. Kollár, “Severi–Brauer varieties: A geometric treatment,” Preprint (2016). arXiv:1606.04368.
C. Shramov and V. Vologodsky, “Boundedness for finite subgroups of linear algebraic groups,” Preprint (2020). arXiv:2009.14485.
C. A. Shramov, “Birational automorphisms of Severi–Brauer surfaces,” Sb. Math. 211 (3), 466–480 (2020).
C. A. Shramov, “Non-abelian groups acting on Severi–Brauer surfaces,” Math. Notes 108 (6), 916–917 (2020).
C. Shramov, “Finite groups acting on Severi–Brauer surfaces,” Eur. J. Math. 7 (2), 591–612 (2021).
G. Castelnuovo, “Sulla razionalità delle involuzioni piane,” Math. Ann. 44, 125–155 (1894).
A. S. Trepalin, “Rationality of the quotient of \({{\mathbb{P}}^{2}}\) by finite group of automorphisms over arbitrary field of characteristic zero,” Cent. Eur. J. Math. 12 (2), 229–239 (2014).
A. Trepalin, “Quotients of del Pezzo surfaces,” Int. J. Math. 30 (11), 1950068 (2019).
S. Gorchinskiy and C. Shramov, Unramified Brauer Group and Its Applications (Am. Math. Soc., Providence, 2018).
S. A. Amitsur, “Generic splitting fields of central simple algebras,” Ann. Math. 62 (2), 8–43 (1955).
C. Shramov, “Automorphisms of cubic surfaces without points,” Int. J. Math. 31 (11), 2050083 (2020).
V. A. Iskovskikh, “Factorization of birational mappings of rational surfaces from the point of view of Mori theory,” Russ. Math. Surv. 51 (4), 585–652 (1996).
ACKNOWLEDGMENTS
The author is grateful to Costya Shramov and Sergey Gorchinskiy for many useful discussions and comments.
Funding
The study has been funded within the framework of the HSE University Basic Research Program.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
The authors declare that they have no conflicts of interest.
Rights and permissions
About this article
Cite this article
Trepalin, A.S. Quotients of Severi–Brauer Surfaces. Dokl. Math. 104, 390–393 (2021). https://doi.org/10.1134/S106456242106017X
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S106456242106017X