We classify complex compact parallelizable manifolds which admit flat torsion free holomorphic affine connections. We exhibit complex compact manifolds admitting holomorphic affine connections, but no flat torsion free holomorphic affine connections.
Study of affine and projective structures on foliated complex manifolds.
problem Formalizing and analyzing affine and projective structures on foliations.
method Formalizing concepts, providing local normal forms, proving index formulae, classifying structures.
result Compact algebraic manifolds of even dimension do not admit foliated projective structures.
The paper constructs submanifolds with corners in Delzant polytopes from affine subspaces.
problem Understanding submanifolds with corners in Delzant polytopes.
method Constructing submanifolds with corners in Delzant polytopes from affine subspaces.
result Conditions for submanifolds with corners are equivalent to those for torus-equivariantly embedded toric manifolds.
We prove that any compact complex manifold with finite fundamental group and algebraic dimension zero admits no holomorphic affine connection.
Flat affine subvarieties found in OT-manifolds.
problem Characterizing subvarieties in Oeljeklaus-Toma manifolds.
method Analyzing the structure of Oeljeklaus-Toma manifolds using number-theoretic data.
result Any complex subvariety of smallest possible positive dimension in an OT-manifold is flat affine.
New complex manifolds found with flat structure.
problem Finding compact complex manifolds with flat affine structure.
method Using Lie groups with left-invariant complex structure.
result Retrieved Inoue surfaces S+ in 2D. Study shows complex affine transformations index is at most 2 for Kähler manifolds.
problem Understanding transformations on Kähler manifolds.
method Analyzing groups of transformations on Kähler manifolds.
result Establishes a stronger version of Yano-Obata conjecture for complete Kähler manifolds.
The paper classifies compact affine quaternionic curves and surfaces.
problem Classifying compact affine quaternionic curves and surfaces.
method Affine quaternionic manifolds, Kodaira Theorem, fundamental groups, Lie Groups.
result Only quaternionic tori and primary Hopf surface S^3 x S^1 are compact affine quaternionic curves.
The study explores extensions of Kähler manifolds and their properties.
problem Analyzing extensions of Kähler manifolds and their properties.
method Formulating conditions for affine bundles and studying their properties.
result Established a relation to adapted complex structures and good complexifications.
Affine connections linked to Riccati distributions on compact surfaces.
problem Understanding affine structures on complex compact surfaces.
method Established a correspondence between affine connections and Riccati distributions.
result One-to-one correspondence between affine structures and Riccati foliations on compact surfaces.
We develop a theory of stable bundles and affine Hermitian-Einstein metrics for flat vector bundles over a special affine manifold (a manifold admitting an atlas whose gluing maps are all locally constant volume-preserving affine maps). Our paper presents a parallel to Donaldson-Uhlenbeck-Yau's proof of the existence o…
We obtain a characterization of the real Lie algebras admitting abelian complex structures in terms of certain affine Lie algebras aff(A), where A is a commutative algebra. These affine Lie algebras are natural generalizations of aff(C) and the corresponding Lie grou…
Complex foliation cohomology is shown to be simple.
problem Analyzing cohomology of a specific complex foliation.
method Explicitly computed the Dolbeault cohomology in degree 1.
result Foliated Dolbeault cohomology in degree 1 is isomorphic to C.
Affine vector fields on pseudo-Kähler manifolds are symplectic.
problem Characterize affine vector fields on compact pseudo-Kähler manifolds.
method Two proofs provided, showing affine vector fields are symplectic and discuss properties of Lie derivatives.
result Affine vector fields on compact pseudo-Kähler manifolds are symplectic.
Proves algebraic cones for LCK manifolds with potential.
problem Characterizing algebraic cones for LCK manifolds.
method Analyzes LCK manifolds as complex submanifolds of Hopf manifolds and covers, proving algebraicity of the resulting cones.
result Affine algebraic structure on cones is independent of manifold choice.
Study intrinsic volume forms on complex hypersurfaces.
problem Computing volume functionals on pseudoconvex hypersurfaces.
method Compute first and second variation formulae, explore infinite dimensional aspects.
result Discuss possible analogues of the affine isoperimetric inequality.
Study of flows on complex manifolds with holomorphic properties.
problem Global rigidity of transversely holomorphic Anosov flows on smooth compact manifolds.
method Analyzing the integrability of unstable and stable distributions, proving uniqueness in low dimensions.
result For topologically transitive flows, they are either orbit equivalent to a hyperbolic automorphism or geodesic flow.
The goal of this paper is to introduce the lifting theory that has an important role in geometry. Therefore, using the lifts of differential geometric structures we show that tangent bundle TM of paracomplex manifold M admits para-complex torsion-free affine connection.
Our aim here is to investigate the holomorphic geometric structures on compact complex manifolds which may not be Kähler. We prove that holomorphic geometric structures of affine type on compact Calabi-Yau manifolds with polystable tangent bundle (with respect to some Gauduchon metric on it) are locally homogeneous. In…
Study on holomorphic structures on complex manifolds with specific properties.
problem Holomorphic geometric structures on complex manifolds with vanishing first Chern class.
method Proves properties of holomorphic geometric structures on compact complex manifolds.
result Holomorphic geometric structures are locally homogeneous for certain manifolds.
This paper is the first arising from our project announced in math.AG/0211094, "Affine manifolds, log structures, and mirror symmetry." We aim to study mirror symmetry by studying the log structures of Illusie-Fontaine and Kato on degenerations of Calabi-Yau manifolds. The basic idea is that one can associate to certai…
The study limits the cohomological dimension of certain affine manifolds with partially hyperbolic holonomy groups.
problem Understanding cohomological dimensions of affine manifolds with specific holonomy groups.
method Analyzing the tangent bundle structure and using coarse geometry techniques.
result The cohomological dimension is bounded by the dimension minus the index of the holonomy group.
It is proved that the moduli space of all connected compact orientable embedded minimal affine Lagrangian submanifolds of a complex equiaffine space constitutes an infinite dimensional Frechet manifold (if it is not the empty set). The moduli space of all connected compact orientable metric Lagrangian embedded surfaces…
Study of polygon degeneration to segments in complex space.
problem Understanding the space of polygons degenerated to segments.
method Proved L(n) is a smooth submanifold, described its topology, computed geodesics, and quotiented the space. result Found that L(n) and M(n) contain straight lines forming a basis of directions in their tangent spaces. We introduce the notion of a special complex manifold: a complex manifold (M,J) with a flat torsionfree connection \nabla such that (\nabla J) is symmetric. A special symplectic manifold is then defined as a special complex manifold together with a \nabla-parallel symplectic form ω. This generalises Freed's definition …
An affine manifold is a manifold with torsion-free flat affine connection. A geometric topologist's definition of an affine manifold is a manifold with an atlas of charts to the affine space with affine transition functions; a radiant affine manifold is an affine manifold with holonomy consisting of affine transformati…
Complex manifolds with specific geometric structures have infinite fundamental groups.
problem Characterizing complex manifolds with holomorphic Cartan geometries.
method Analyzing the fundamental group of complex manifolds with holomorphic Cartan geometries of algebraic type.
result Compact complex manifolds of algebraic dimension zero with holomorphic Cartan geometries of algebraic type have infinite fundamental groups.
Leibniz cohomology reveals connections on manifolds.
problem Understanding connections on Riemannian manifolds using Leibniz cohomology.
method Expressing Levi-Civita connection as a cochain in Leibniz cohomology of vector fields.
result Vanishing of Leibniz coboundary implies eigenfunctions of the Laplacian.
Study on non-Kähler Calabi-Yau manifolds and their geometric structures.
problem Holomorphic geometric structures on non-Kähler compact complex manifolds.
method Beauville-Bogomolov decomposition and weak Bochner principle.
result Rigidity of Vaisman Calabi-Yau manifolds implies they are Kodaira manifolds.
New iteration method for complex and real Monge-Ampere equations converges under certain conditions.
problem Proving convergence of Monge-Ampere iterations for complex and real equations.
method Introduced Monge-Ampere iteration for real equations, established convergence conditions, and provided geometric applications.
result Established sufficient conditions for convergence of Monge-Ampere iteration and provided geometric applications.
We construct finite volume hyperbolic manifolds with large symmetry groups. The construction makes use of the presentations of finite Coxeter groups provided by Barot and Marsh and involves mutations of quivers and diagrams defined in the theory of cluster algebras. We generalize our construction by assigning to every …
A general theorem on the existence of natural torsion-free affine connections on a complete family of compact complex submanifolds in a complex manifold is proved. Applications to twistor theory are discussed.
A (flat) affine 3-manifold is a 3-manifold with an atlas of charts to an affine space R3 with transition maps in the affine transformation group Aff(R3). We will show that a connected closed affine 3-manifold is either an affine Hopf 3-manifold or decomposes canonically to conca…
The paper studies Anosov holonomy groups in complete affine manifolds.
problem Characterizing Anosov holonomy groups in complete affine manifolds.
method Representation theory and coarse geometry techniques.
result Complete affine manifolds with Anosov holonomy groups have specific geometric properties.
To every real analytic Riemannian manifold M there is associated a complex structure on a neighborhood of the zero section in the real tangent bundle of M. This structure can be uniquely specified in several ways, and is referred to as a Grauert tube. We say that a Grauert tube is entire if the complex structure can be…
An (flat) affine 3-manifold is a 3-manifold with an atlas of charts to an affine space R3 with transition maps in the affine transformation group Aff(R3). Equivalently an affine 3-manifold is a 3-manifold with a flat torsion-free affine connection. We show that a closed affine 3-mani…
We study affine maps between affine manifolds. Even when the fibers are compact and diffeomorphic, two of them can inherit different affine structures from the source space. This leads to a fixed linear holonomy deformation theory of the affine structure of an affine manifold. We found various conditions which make the…
This paper describes integral affine structures on compact 3-manifolds.
problem Understanding integral affine structures on compact 3-manifolds.
method Analyzing complete integral affine structures on compact 3-manifolds up to finite-sheeted coverings.
result A complete list of integral affine structures on the three-dimensional torus and compact three-dimensional nilmanifolds was obtained.
Characterizes affine vector fields on Finsler manifolds with rigidity results.
problem Understanding affine vector fields on Finsler manifolds.
method Utilizing the Jacobi type equation and spray characterization, proving rigidity theorems.
result Rigidity theorems for affine vector fields on Finsler manifolds with non-positive total Ricci curvature.
Characterizes flat affine connections on manifolds.
problem Understanding flat affine connections on manifolds.
method Characterization through natural affine representation of diffeomorphisms.
result Group of affine transformations acts on R^n with open orbit when dimension > n.
Study of symmetries in deformed q-map spaces reveals a complex group structure.
problem Understanding the symmetries of deformed q-map spaces.
method Analyzing the group of isometries in deformed q-map spaces, focusing on the semidirect product structure.
result The group of isometries always contains a semidirect product of an affine group and a Heisenberg group.
Let M be a compact connected special flat affine manifold without boundary equipped with a Gauduchon metric g and a covariant constant volume form. Let G be either a connected reductive complex linear algebraic group or the real locus of a split real form of a complex reductive group. We prove that a flat princip…
In this paper, we show that a compact affine manifold endowed with an Affine Anosov transformation is finitely covered by a complete affine nilmanifold.
The study compares Kähler and Riemannian normal coordinates on manifolds.
problem Understanding the differences and similarities between Kähler and Riemannian normal coordinates.
method Developed an algorithm to calculate the difference between Kähler and Riemannian normal coordinates as a universal power series in curvature tensor and its derivatives.
result The difference between Kähler and Riemannian normal coordinates is a universal power series in curvature tensor and its derivatives.
Paper proves certain closed affine manifolds without invariant lines don't exist.
problem Proving non-existence of closed affine manifolds with invariant lines.
method Developing map, holonomy, invariant line, large open subsets, modified proof.
result Developing image cannot meet invariant line if affine holonomy acts purely by translations.
Completed classification of rank 2 affine manifolds in genus 3.
problem Classifying rank 2 affine manifolds in genus 3.
method Classification through moduli space of translation surfaces.
result Completed classification of higher rank affine manifolds in genus 3.
This is an extended example of the study of mirror symmetry via log schemes and the discrete Legendre transform on affine manifolds, introduced by myself and Bernd Siebert in "Mirror Symmetry via Logarithmic Degeneration Data I" (math.AG/0309070). In this paper, I consider the construction as it applies to the Batyrev-…
The paper characterizes flat affine connections on manifolds and Lie groups.
problem Characterizing flat affine connections on manifolds and Lie groups.
method New characterization through affine representations of automorphisms.
result Existence of a Lie group with a flat affine bi-invariant connection.