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Related papers: Smooth Families of Tori and Linear K\"ahler Groups

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We describe the equivariant cohomology ring of rationally smooth projective embeddings of reductive groups. These embeddings are the projectivizations of reductive monoids. Our main result describes their equivariant cohomology in terms of…

Algebraic Geometry · Mathematics 2015-07-21 Richard Gonzales

We show that isomorphism classes $[\mathcal{A}]$ of flat $q\times q$ matrix bundles $\mathcal{A}$ (or projectively flat rank-$q$ complex vector bundles $\mathcal{E}$) on a pro-torus $\mathbb{T}$ are in bijective correspondence with the…

Algebraic Topology · Mathematics 2025-09-23 Alexandru Chirvasitu

The paper presents a classification theorem for the class of flat connections with triangular (0,1)-components on a topologically trivial complex vector bundle over a compact Kahler manifold. As a consequence we obtain several results on…

Differential Geometry · Mathematics 2007-05-23 Alexander Brudnyi

This article generalises to K\"ahler orbifolds general results on uniformisation of compact K\"ahler manifolds such as the Shafarevich conjecture for linear fundamental groups.

Algebraic Geometry · Mathematics 2013-02-21 Philippe Eyssidieux

The Leit-Faden of the article (which is partially a survey) is a negative answer to the question whether, for a compact complex manifold which is a $K(\pi, 1)$ the diffeomorphism type determines the deformation type. We show that a…

Algebraic Geometry · Mathematics 2007-05-23 Fabrizio M. E. Catanese

The K-rings of non-singular complex pro jective varieties as well as quasi- toric manifolds were described in terms of generators and relations in an earlier work of the author with V. Uma. In this paper we obtain a similar description for…

Algebraic Topology · Mathematics 2007-07-12 Parameswaran Sankaran

We show that a compact Kaehler manifold X is a complex torus if both the continuous part and discrete part of some automorphism group G of X are infinite groups, unless X is bimeromorphic to a non-trivial G-equivariant fibration. Some…

Algebraic Geometry · Mathematics 2018-09-24 Baohua Fu , De-Qi Zhang

We prove that for every reductive algebraic group $H$ with centre of positive dimension and every integer $K$ there is a smooth and projective variety $X$ and an algebraic $H$-torsor $P \to X$ such that the classifying map $X \to \Bclass H$…

Algebraic Geometry · Mathematics 2009-05-12 Torsten Ekedahl

The Losev-Manin moduli space parametrizes pointed chains of projective lines. In this paper we study a possible generalization to families of pointed degenerate toric varieties. Geometric properties of these families, such as flatness and…

Algebraic Geometry · Mathematics 2022-04-14 Sandra Di Rocco , Luca Schaffler

In this paper we present another notion of a smooth manifold with corners and relate it to the commonly used concept in the literature. Afterwards we introduce complex manifolds with corners and show that if $M$ is a compact (respectively…

Differential Geometry · Mathematics 2010-01-04 Christoph Wockel

Let $\pi\cln X\to \Delta^m$ be a proper smooth K\"ahler morphism from a complex manifold $X$ to the unit polydisc $\Delta^m$. Suppose the fibers over the complement of a proper analytic subset are biholomorphic to a fixed projective…

Algebraic Geometry · Mathematics 2026-05-11 Mu-Lin Li , Xiao-Lei Liu

We study smooth foliations of arbitrary codimension on homogeneous compact K\"ahler manifolds. We prove that smooth foliations on rational compact homogeneous manifolds are locally trivial fibrations and classify the smooth foliations with…

Algebraic Geometry · Mathematics 2015-01-20 Federico Lo Bianco , Jorge Vitorio Pereira

A group morphism is constructed, which can be realized as the induced morphism of fundamental groups from a holomorphic map between compact Kahler manifolds, but can not be realized by a holomorphic map between smooth projective varieties.…

Algebraic Geometry · Mathematics 2010-10-26 Botong Wang

In this paper, we prove that a compact K\"ahler manifold $X$ with semi-positive holomorphic sectional curvature admits a locally trivial fibration $\phi \colon X \to Y$, where the fiber $F$ is a rationally connected projective manifold and…

Differential Geometry · Mathematics 2025-02-04 Shin-ichi Matsumura

We study the proalgebraic space which is the inverse limit of all finite branched covers over a normal toric variety with branching set the invariant divisor under the algebraic torus action. These are completions (compactifications) of the…

Algebraic Geometry · Mathematics 2021-11-16 Juan M. Burgos , Alberto Verjovsky

We introduce the category of {\it locally $k$-standard $T$-manifolds} which includes well-known classes of manifolds such as toric and quasitoric manifolds, good contact toric manifolds and moment-angle manifolds. They are smooth manifolds…

Algebraic Topology · Mathematics 2022-01-05 Soumen Sarkar , Jongbaek Song

We characterize the smooth toric varieties for which the Merkurjev spectral sequence, connecting equivariant and ordinary K-theory, degenerates. We find under which conditions on the support of the fan the $E^2$ terms of the spectral…

Algebraic Geometry · Mathematics 2007-05-23 Silvano Baggio

To a smooth projective variety $X$ whose Chow group of $0$-cycles is $\mathbf Q$-universally trivial one can associate its torsion index $\mathrm{Tor}(X)$, the smallest multiple of the diagonal appearing in a cycle-theoretic decomposition…

Algebraic Geometry · Mathematics 2017-12-20 Bruno Kahn , with an appendix by Jean-Louis Colliot-Thélène

We introduce an exact category of torsion-free constructible tori and an abelian category of constructible tori over a Dedekind scheme with perfect residue fields. The first one has an explicit description as $2$-term complexes of smooth…

Algebraic Geometry · Mathematics 2025-05-07 Adrien Morin , Takashi Suzuki

We construct the first non-trivial examples of complete families of non-degenerate smooth space curves, and show that the base of such a family cannot be a rational curve. Both results rely on the study of the strong semistability of…

Algebraic Geometry · Mathematics 2019-11-11 Olivier Benoist