English
Related papers

Related papers: Non-abelian real Hodge theory for proper varieties

200 papers

We revisit the procedure of deformation of $C^*$-algebras via coactions of locally compact groups and extend the methods to cover deformations for maximal, reduced, and exotic coactions for a given group $G$ and circle-valued Borel…

Operator Algebras · Mathematics 2025-02-05 Alcides Buss , Siegfried Echterhoff

We show that the cycle map on a variety X, from algebraic cycles modulo algebraic equivalence to integer cohomology, lifts canonically to a topologically defined quotient of the complex cobordism ring of X. This more refined cycle map gives…

alg-geom · Mathematics 2008-02-03 Burt Totaro

We use coverings by smooth projective varieties then apply nonabelian Hodge techniques to study the topology of proper Deligne-Mumford stacks as well as more general simplicial varieties.

Algebraic Geometry · Mathematics 2010-10-19 Carlos T. Simpson

Let G be a complex reductive Lie group acting on a compact K\"ahler manifold X and assume that the action of a maximal compact subgroup K of G is Hamiltonian. For each extreme point of the convex hull of the momentum map image, there is an…

Complex Variables · Mathematics 2025-05-13 Peter Heinzner , Christian Zöller

The notion of Lie $H$-pseudoalgebra is a higher-dimensional analogue of Lie conformal algebras. In this paper, we classify the equivalence classes of non-abelian extensions of a Lie $H$-pseudoalgebra $L$ by another Lie $H$-pseudoalgebra $M$…

Representation Theory · Mathematics 2023-12-19 Apurba Das

Let $X$ be a simply connected closed oriented manifold of rationally elliptic homotopy type. We prove that the string topology bracket on the $S^1$-equivariant homology $\overline{H}_{\ast}^{S^1}(\mathcal{L}X,\mathbb{Q}) $ of the free loop…

Quantum Algebra · Mathematics 2021-07-01 Yuri Berest , Ajay C. Ramadoss , Yining Zhang

We construct Hodge filtered cohomology groups for complex manifolds that combine the topological information of generalized cohomology theories with geometric data of Hodge filtered holomorphic forms. This theory provides a natural…

Algebraic Topology · Mathematics 2017-05-17 Michael J. Hopkins , Gereon Quick

We present necessary and sufficient conditions for a group homomorphism between spaces of smooth sections of Lie group bundles to be a weighted composition operator. These results provide new insights into a wide range of problems related…

Differential Geometry · Mathematics 2025-02-03 Ning Zhang

Let $K$ be a finite extension of the $p$-adic numbers $\mathbb Q_p$ with ring of integers $\mathcal O_K$, $\mathcal X$ a regular scheme, proper, flat, and geometrically irreducible over $\mathcal O_K$ of dimension $d$, and $\mathcal X_K$…

Number Theory · Mathematics 2022-11-28 Thomas H. Geisser , Baptiste Morin

We prove that strongly homotopy algebras (such as $A_\infty$, $C_\infty$, sh Lie, $B_\infty$, $G_\infty$,...) are homotopically invariant in the category of chain complexes. An important consequence is a rigorous proof that `strongly…

Algebraic Topology · Mathematics 2007-05-23 Martin Markl

A noetherian form is an abstract self-dual framework suitable for establishing homomorphism theorems (such as the isomorphism theorems and homological diagram lemmas) for group-like structures. In this paper we identify and carry out an…

Category Theory · Mathematics 2025-01-29 Zurab Janelidze , Francois van Niekerk

We study the topology of compact manifolds with a Lie group action for which there are only finitely many non-principal orbits, and describe the possible orbit spaces which can occur. If some non-principal orbit is singular, we show that…

Differential Geometry · Mathematics 2011-06-20 Stefan Bechtluft-Sachs , David J. Wraith

We show local and cocycle rigidity for $\R^k \times \Z^l$ partially hyperbolic translation actions on homogeneous spaces $\mc G/ \Lambda$. We consider a large class of actions whose geometric properties are more complicated than previously…

Dynamical Systems · Mathematics 2017-05-02 Kurt Vinhage , Zhenqi Jenny Wang

Exact categories are a natural generalisation of abelian categories and provide a fertile ground to develop relative homological algebra. In this paper, starting from a class of relative Gorenstein projective objects in an exact category…

Representation Theory · Mathematics 2026-02-27 Anastasios Slaftsos , Jorge Vitória

Given a Hopf algebra $A$ graded by a discrete group together with an action of the same group preserving the grading, we define a new Hopf algebra, which we call the graded twisting of $A$. If the action is adjoint, this new Hopf algebra is…

Quantum Algebra · Mathematics 2021-06-10 Julien Bichon , Sergey Neshveyev , Makoto Yamashita

Let $X$ be an irreducible complex analytic space with $j:U\into X$ an immersion of a smooth Zariski open subset, and let $\bV$ be a variation of Hodge structure of weight $n$ over $U$. Assume $X$ is compact K\"ahler. Then provided the local…

Algebraic Geometry · Mathematics 2008-12-12 Chris Peters , Morihiko Saito

CM-type projective varieties X of complex dimension n are characterized by their CM-type rational Hodge structures on the cohomology groups. One may impose such a condition in a weakest form when the canonical bundle of X is trivial; the…

Algebraic Geometry · Mathematics 2024-01-25 Masaki Okada , Taizan Watari

Given a suitable action on a complex projective variety X of a non-reductive affine algebraic group H, this paper considers how to choose a reductive group G containing H and a projective completion of G x_H X which is a reductive envelope…

Algebraic Geometry · Mathematics 2008-12-15 Frances Kirwan

We prove that affine invariant manifolds in strata of flat surfaces are algebraic varieties. The result is deduced from a generalization of a theorem of M\"oller. Namely, we prove that the image of a certain twisted Abel-Jacobi map lands in…

Dynamical Systems · Mathematics 2017-10-31 Simion Filip

The goal of this paper is to first define a Hodge theoretic fundamental group for smooth connected complex algebraic varieties and then prove and study a right exact sequence of Hodge theoretic fundamental groups associated to a smooth…

Algebraic Geometry · Mathematics 2025-10-22 Simon Shuofeng Xu