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Related papers: Cremona groups of real surfaces

200 papers

The generators of the group of birational automorphisms of any Severi-Brauer surface non-isomorphic over an algebraically non-closed field to the projective plane are explicitly described.

Algebraic Geometry · Mathematics 2023-06-22 Felix Weinstein

We find a set of generators for the automorphism group of a graph product of finitely generated abelian groups entirely from a certain labeled graph. In addition, we find generators for the important subgroup of star-automorphisms defined…

Group Theory · Mathematics 2009-11-04 Luis Corredor , Mauricio Gutierrez

We prove that a finite $3$-group in the Cremona group $\mathrm{Cr}_3(\mathbb{C})$ can be generated by at most $4$ elements. This provides the last missing piece in bounding the ranks of finite $p$-subgroups in the space Cremona group.

Algebraic Geometry · Mathematics 2021-05-05 Konstantin Loginov

This survey deals with the Cremona group via its subgroups.

Algebraic Geometry · Mathematics 2021-11-04 Julie Déserti

This article studies the group generated by automorphisms of the projective space of dimension $n$ and by the standard birational involution of degree $n$. Every element of this group only contracts rational hypersurfaces, but in odd…

Algebraic Geometry · Mathematics 2019-02-14 Jérémy Blanc , Isac Hedén

The first group of results of this paper concerns the compressibility of finite subgroups of the Cremona groups. The second concerns the embeddability of other groups in the Cremona groups and, conversely, the Cremona groups in other…

Algebraic Geometry · Mathematics 2020-01-08 Vladimir L. Popov

Two birational subvarieties of P^n are called Cremona equivalent if there is a Cremona modification of P^n mapping one to the other. If the codimension of the varieties is at least 2 then they are always Cremona Equivalent. For divisors the…

Algebraic Geometry · Mathematics 2020-07-30 Massimiliano Mella

In this note we provide explicit generators of the Picard groups of cyclic Brauer-Severi varieties defined over the base field. In particular, for all Brauer-Severi surfaces. To produce these generators we use the Twisting Theory for smooth…

Number Theory · Mathematics 2017-07-03 Eslam Badr , Francesc Bars , Elisa Lorenzo Garcia

We show that the real Cremona group of the plane is a non-trivial amalgam of two groups amalgamated along their intersection and give an alternative proof of its abelianisation.

Algebraic Geometry · Mathematics 2019-12-03 Susanna Zimmermann

We show that plane Cremona groups over finite fields embed as dense subgroups into Neretin groups, i.e. groups of almost automorphisms of rooted trees. We also show that if the finite base field has even characteristic and contains at least…

Group Theory · Mathematics 2023-01-13 Anthony Genevois , Anne Lonjou , Christian Urech

The plane Cremona group over the finite field $\mathbb{F}_2$ is generated by three infinite families and finitely many birational maps with small base orbits. One family preserves the pencil of lines through a point, the other two preserve…

Algebraic Geometry · Mathematics 2024-02-08 Julia Schneider

We give the classification of the maximal infinite algebraic subgroups of the real Cremona group of the plane up to conjugacy and present a parametrisation space of each conjugacy class. Moreover, we show that the real plane Cremona group…

Algebraic Geometry · Mathematics 2016-12-02 Maria Fernanda Robayo , Susanna Zimmermann

We study large groups of birational transformations Bir(X), where X is a variety of dimension at least 3, defined over C or a subfield of C. Two prominent cases are when X is the projective space, in which case Bir(X) is the Cremona group…

Algebraic Geometry · Mathematics 2021-10-08 Jérémy Blanc , Stéphane Lamy , Susanna Zimmermann

We give a simple set of generators and relations for the Cremona group of the plane. Namely, we show that the Cremona group is the amalgamated product of the de Jonqui\`eres group with the group of automorphisms of the plane, divided by one…

Algebraic Geometry · Mathematics 2013-03-22 Jérémy Blanc

We show that the alternating groups $\mathfrak{A}_5$ and $\mathfrak{A}_6$ are the only finite simple non-abelian subgroups of the group of birational selfmaps of the real three-dimensional projective space.

Algebraic Geometry · Mathematics 2025-11-17 Ivan Cheltsov , Antoine Pinardin , Yuri Prokhorov

This paper is concerned with suitable generalizations of a plane de Jonqui\`eres map to higher dimensional space $\mathbb{P}^n$ with $n\geq 3$. For each given point of $\mathbb{P}^n$ there is a subgroup of the entire Cremona group of…

Algebraic Geometry · Mathematics 2019-08-15 Ivan Pan , Aron Simis

Let $\Cr_\Q(2)$ be the Cremona group of rank $2$ over rational numbers. we give a classification of large finite subgroups $G$ of $\Cr_\Q(2)$ and give a new sharp bound smaller (but not multiplicative) than $M(\Q)=120960 =…

Algebraic Geometry · Mathematics 2026-01-14 Ahmed Abouelsaad

We use a recent advance in birational geometry to prove new lower bounds on the essential dimension of some finite groups.

Algebraic Geometry · Mathematics 2018-03-28 Zinovy Reichstein

We show that any infinite algebraic subgroup of the plane Cremona group over a perfect field is contained in a maximal algebraic subgroup of the plane Cremona group. We classify the maximal groups, and their subgroups of rational points, up…

Algebraic Geometry · Mathematics 2024-12-11 Julia Schneider , Susanna Zimmermann

In this article we prove that the full automorphism group of a cyclic $p$-gonal pseudo-real Riemann surface of genus $g$ is either a semidirect product $C_{n}\ltimes C_{p}$ or a cyclic group, where $p$ is a prime $>2$ and $g>(p-1)^{2}$. We…

Algebraic Geometry · Mathematics 2015-03-16 Emilio Bujalance , Antonio F. Costa