English
Related papers

Related papers: Virtually abelian K\"ahler and projective groups

200 papers

First we show that any group of automorphisms of null-entropy of a projective hyperk\"ahler manifold $M$ is almost abelian of rank at most $\rho(M) - 2$. We then characterize automorphisms of a K3 surface with null-entropy and those with…

Algebraic Geometry · Mathematics 2007-05-23 Keiji Oguiso

Let $X$ be a compact K{\"a}hler manifold of dimension three. We prove that there exists a projective manifold $Y$ such that $\pi\_1(X)\simeq \pi\_1(Y)$. We also prove the bimeromorphic existence of algebraic approximations for compact…

Algebraic Geometry · Mathematics 2020-01-08 Benoît Claudon , Andreas Höring , Hsueh-Yung Lin

A theorem of A. Weil asserts that a topological group embeds as a (dense) subgroup of a locally compact group if and only if it contains a non-empty precompact open set; such groups are called locally precompact. Within the class of locally…

General Topology · Mathematics 2010-05-05 W. W. Comfort , G. Lukács

Let $G$ be a non-compact classical semisimple Lie group and let $G/V$ be the adjoint orbit with respect to a fixed element in $G$. These manifolds can be equipped with an almost-K\"ahler structure and we provide explicit formulae for the…

Combinatorics · Mathematics 2022-09-30 Alice Gatti

Motivated by constructions appearing in mirror symmetry, we study special representatives of complexified K\"ahler classes, which extend the notions of constant scalar curvature and extremal representatives for usual K\"ahler classes. In…

Differential Geometry · Mathematics 2024-04-18 Carlo Scarpa , Jacopo Stoppa

In this note, we study the normal compact K\"ahler (possibly singular) threefold $X$ admitting the action of a free abelian group $G$ of maximal rank, all the non-trivial elements of which are of positive entropy. If such $X$ is further…

Algebraic Geometry · Mathematics 2022-03-21 Guolei Zhong

We consider two variants of those Abelian groups with all proper strongly invariant subgroups isomorphic and give an in-depth study of their basic and specific properties in either parallel or contrast to the Abelian groups with all proper…

Group Theory · Mathematics 2023-08-01 Andrey R. Chekhlov , Peter V. Danchev

We give a homological characterisation of relatively prosolvable projective groups.

Group Theory · Mathematics 2022-10-05 Pavel Zalesskii

Let $\Gamma$ be a finitely generated torsion-free group. We show that the statement of $\Gamma$ being virtually abelian is equivalent to the statement that the $*$-regular closure of the group ring $\mathbb{C}[\Gamma]$ in the algebra of…

Group Theory · Mathematics 2023-03-07 Joan Claramunt , Lukasz Grabowski

We consider linear groups which do not contain unipotent elements of infinite order, which includes all linear groups in positive characteristic, and show that this class of groups has good properties which resemble those held by groups of…

Group Theory · Mathematics 2018-11-04 J. O. Button

We show that for any complete connected K\"ahler manifold the index of the group of complex affine transformations in the group of c-projective transformations is at most two unless the K\"ahler manifold is isometric to complex projective…

Differential Geometry · Mathematics 2021-06-08 Vladimir S. Matveev , Katharina Neusser

In this paper we prove a characterization of quotients of Abelian varieties by the actions of finite groups that are free in codimension-one via some vanishing conditions on the orbifold Chern classes. The characterization is given among a…

Algebraic Geometry · Mathematics 2016-10-18 Steven Lu , Behrouz Taji

Let $M$ be a K\"ahler manifold with complex structure $J$ and K\"ahler metric $g$. A c-projective vector field is a vector field on $M$ whose flow sends $J$-planar curves to $J$-planar curves, where $J$-planar curves are analogs of what…

Differential Geometry · Mathematics 2025-05-09 Gianni Manno , Jan Schumm , Andreas Vollmer

As a special case of perspective R-modules, an Abelian goup is called perspective if isomorphic summands have a common complement. In this paper we describe many classes of such groups.

Group Theory · Mathematics 2024-03-28 Grigore Calugareanu , Andrey Chekhlov

We consider central simple $K$-algebras which happen to bedifferential graded $K$-algebras. Two such algebras $A$ and $B$are considered equivalent if there are bounded complexes of finite dimensional$K$-vector spaces $C_A$ and $C_B$ such…

Rings and Algebras · Mathematics 2023-08-21 Alexander Zimmermann

We consider actions of reductive complex Lie groups $G=K^C$ on K\"ahler manifolds $X$ such that the $K$--action is Hamiltonian and prove then that the closures of the $G$--orbits are complex-analytic in $X$. This is used to characterize…

Complex Variables · Mathematics 2012-11-15 Bruce Gilligan , Christian Miebach , Karl Oeljeklaus

We give a condition on the defining graph of a right-angled Artin group which implies its automorphism group is virtually indicable, that is, it has a finite-index subgroup that admits a homomorphism onto $\Z$. We use this as part of a…

Group Theory · Mathematics 2020-11-10 Andrew Sale

We obtain characterizations and structure results for homogeneous principal bundles over abelian varieties, that generalize work of Miyanishi and Mukai on homogeneous vector bundles. For this, we rely on notions and methods of algebraic…

Algebraic Geometry · Mathematics 2011-06-30 Michel Brion

Let $A$ be an abelian variety over the function field $K$ of a curve over a finite field. We describe several mild geometric conditions ensuring that the group $A(K^{\rm perf})$ is finitely generated and that the $p$-primary torsion…

Algebraic Geometry · Mathematics 2020-07-15 Damian Rössler

For an abelian surface $A$, we consider stable vector bundles on a generalized Kummer variety $K_n(A)$ with $n>1$. We prove that the connected component of the moduli space which contains the tautological bundles associated to line bundles…

Algebraic Geometry · Mathematics 2024-09-16 Andreas Krug , Fabian Reede , Ziyu Zhang