English
Related papers

Related papers: A decomposition theorem for singular spaces with t…

200 papers

In this paper we show that any smoothable complex projective variety, smooth in codimension two, with klt singularities and numerically trivial canonical class admits a finite cover, \'etale in codimension one, that decomposes as a product…

Algebraic Geometry · Mathematics 2017-04-07 Stéphane Druel , Henri Guenancia

The classical Beauville-Bogomolov Decomposition Theorem asserts that any compact K\"ahler manifold with numerically trivial canonical bundle admits an \'etale cover that decomposes into a product of a torus, and irreducible,…

Algebraic Geometry · Mathematics 2016-11-08 Daniel Greb , Stefan Kebekus , Thomas Peternell

Let $X$ be a compact K\"ahler fourfold with klt singularities and vanishing first Chern class, smooth in codimension two. We show that $X$ admits a Beauville-Bogomolov decomposition: a finite quasi-\'etale cover of $X$ splits as a product…

Algebraic Geometry · Mathematics 2024-06-04 Patrick Graf

We investigate the holonomy group of singular K\"ahler-Einstein metrics on klt varieties with numerically trivial canonical divisor. Finiteness of the number of connected components, a Bochner principle for holomorphic tensors, and a…

Algebraic Geometry · Mathematics 2020-06-16 Daniel Greb , Henri Guenancia , Stefan Kebekus

We give a simplified proof (in characteristic zero) of the decomposition theorem for complex projective varieties with klt singularities and numerically trivial canonical bundle. The proof rests in an essential way on most of the partial…

Algebraic Geometry · Mathematics 2020-05-13 Frederic Campana

Let $X$ be a compact complex manifold such that its canonical bundle $K_X$ is numerically trivial. Assume additionally that $X$ is Moishezon or $X$ is Fujiki with dimension at most four. Using the MMP and classical results in foliation…

Differential Geometry · Mathematics 2024-09-11 Indranil Biswas , Junyan Cao , Sorin Dumitrescu , Henri Guenancia

Irreducible symplectic manifolds are one of the three building blocks of compact K\"ahler manifolds with numerically trivial canonical bundle by the Beauville-Bogomolov decomposition theorem. There are several singular analogues of…

Algebraic Geometry · Mathematics 2020-03-17 Arvid Perego

Given a p-form defined on the smooth locus of a normal variety, and a resolution of singularities, we study the problem of extending the pull-back of the p-form over the exceptional set of the desingularization. For log canonical pairs and…

Algebraic Geometry · Mathematics 2019-02-20 Daniel Greb , Stefan Kebekus , Sándor J. Kovács

Given a reflexive sheaf on a mildly singular projective variety, we prove a flatness criterion under certain stability conditions. This implies the algebraicity of leaves for sufficiently stable foliations with numerically trivial canonical…

Algebraic Geometry · Mathematics 2018-04-24 Andreas Höring , Thomas Peternell

In this paper, we formulate the geometric Bogomolov conjecture for abelian varieties, and give some partial answers to it. In fact, we insist in a main theorem that under some degeneracy condition, a closed subvariety of an abelian variety…

Algebraic Geometry · Mathematics 2013-01-14 Kazuhiko Yamaki

This paper gives a simple example of a family of Calabi-Yaus of any dimension with canonical singularities of dimension one, whose Kuranishi space is singular. Thus the Bogomolov-Tian-Todorov unobstructedness theorem is not true for…

alg-geom · Mathematics 2008-02-03 Mark Gross

In this paper, we establish a structure theorem for projective klt pairs $(X,\Delta)$ with nef anti-log canonical divisor; specifically, we prove that, up to replacing $X$ with a finite quasi-\'etale cover, $X$ admits a locally trivial…

Algebraic Geometry · Mathematics 2023-08-31 Shin-ichi Matsumura , Juanyong Wang

By a recent result of Viehweg, projective manifolds with ample canonical class have a coarse moduli space, which is a union of quasiprojective varieties. In this paper, we prove that there are manifolds with ample canonical class that lie…

alg-geom · Mathematics 2008-02-03 Barbara Fantechi , Rita Pardini

For every $d \geq 4$, we construct a $d$-dimensional, log canonical, $K$-trivial variety with the property that two general fibers of its Albanese morphism are not birational. This provides a strong counterexample to the…

Algebraic Geometry · Mathematics 2026-05-11 Fabio Bernasconi , Stefano Filipazzi , Zsolt Patakfalvi , Nikolaos Tsakanikas

We describe the possible noncommutative deformations of complex projective three-space by exhibiting the Calabi--Yau algebras that serve as their homogeneous coordinate rings. We prove that the space parametrizing such deformations has…

Quantum Algebra · Mathematics 2014-03-26 Brent Pym

We prove that the geometric Bogomolov conjecture holds for nowhere degenerate abelian varieties of dimension $5$ with trivial trace. By this result together with our previous work, we see that the conjecture holds for an abelian variety…

Algebraic Geometry · Mathematics 2018-01-03 Kazuhiko Yamaki

These lecture notes present a mostly self-contained proof of the singular version of Beauville-Bogomolov decomposition theorem for compact K\"ahler varieties with log terminal singularities and zero first Chern class.

Algebraic Geometry · Mathematics 2025-10-28 Henri Guenancia

This paper first generalises the Bogomolov-Tian-Todorov unobstructedness theorem to the case of Calabi-Yau threefolds with canonical singularities. The deformation space of such a Calabi-Yau threefold is no longer smooth, but the general…

alg-geom · Mathematics 2025-10-10 Mark Gross

We extend the decomposition theorem for numerically $K$-trivial varieties with log terminal singularities to the K\"ahler setting. Along the way we prove that all such varieties admit a strong locally trivial algebraic approximation, thus…

Algebraic Geometry · Mathematics 2022-01-27 Benjamin Bakker , Henri Guenancia , Christian Lehn

We construct canonical semi-orthogonal decompositions for derived categories of smooth projective surfaces. These decompositions are compatible with the operations in the minimal model program, such as blow-ups and conic bundles. Therefore…

Algebraic Geometry · Mathematics 2025-12-05 Alexey Elagin , Julia Schneider , Evgeny Shinder
‹ Prev 1 2 3 10 Next ›