Constructs a map from stable extensions to irreducible metrics on Riemann surfaces.
problem Understanding and constructing cone spherical metrics on Riemann surfaces.
method Using the theory of indigenous bundles, the construction involves developing maps and stable extensions of two line bundles.
result Generically injective map from stable extensions to irreducible metrics, with properties about effective divisors.
Study confirms no Kähler-Einstein edge metrics for certain asymptotically log Fano varieties.
problem Existence of Kähler-Einstein edge metrics on asymptotically log Fano varieties.
method Analyzes properties of asymptotically log Fano varieties and their metrics.
result No Kähler-Einstein edge metrics exist for specified varieties.
Given a compact Kaehler manifold, we consider the complement U of a divisor with normal crossings. We study the variety of unitary representations of the fundamental group of U with certain restrictions related to the divisor. We show that the possible singularities of this variety as well as of the corresponding modul…
Study finds existence and non-uniqueness of cone spherical metrics on compact Riemann surfaces.
problem Existence and non-uniqueness of cone spherical metrics with prescribed singularities.
method Utilizing polystable extensions of line bundles, the study establishes three primary results concerning these metrics.
result Existence of multiple irreducible and reducible cone spherical metrics for certain effective divisors.
Study multiplicity of non-acyclic SL2-representations and L-functions of Whitehead links.
problem Understanding the multiplicity of non-acyclic SL2-representations and their L-functions.
method Geometric interpretation of Reidemeister torsion divisors and application to L-functions.
result Prove multiplicity two for odd-twisted Whitehead links.
Study on Klt varieties with trivial canonical class, focusing on holonomy and stability.
problem Holonomy group of singular Kähler-Einstein metrics on klt varieties with numerically trivial canonical divisor.
method Investigation of holonomy group properties, finiteness of connected components, Bochner principle for holomorphic tensors, and connections between irreducibility of holonomy representations and stability of the tangent sheaf.
result Refinement of known decompositions for tangent sheaves of varieties with trivial canonical divisor, showing that up to finite quasi-étale covers, varieties with strongly stable tangent sheaves are either Calabi-Yau or irreducible holomorphic symplectic.
We investigate the case of the Kahler-Ricci flow blowing down disjoint exceptional divisors with normal bundle O(-k) to orbifold points. We prove smooth convergence outside the exceptional divisors and global Gromov-Hausdorff convergence. In addition, we establish the result that the Gromov-Hausdorff limit coincides wi…
Holomorphic vector fields and anti-canonical divisors on complex manifolds are studied.
problem Existence of non-trivial holomorphic vector fields on compact complex manifolds.
method Vanishing result for measure preserving holomorphic vector fields, Gibbs stability, and log terminal singularities.
result No non-trivial holomorphic vector fields on compact complex manifolds with big anti-canonical line bundle.
New cycles found in moduli space from quadratic differentials.
problem Finding new cycles in moduli space from quadratic differentials.
method Exhibiting rigid and extremal effective codimension j cycles in Mg,n from strata of quadratic differentials. result Infinitely many new rigid and extremal effective codimension j cycles in Mg,n are exhibited. In this note, we report on a work jointly done with C. Simpson on a generalization of Reznikov's theorem which says that the Chern-Simons classes and in particular the Deligne Chern classes (in degrees >1) are torsion, of a flat vector bundle on a smooth complex projective variety. We consider the case of a smooth q…
We consider the connected-sum method of constructing compact Riemannian 7-manifolds with holonomy G_2 developed in math.DG/0012189. The method requires pairs of projective complex threefolds endowed with anticanonical K3 divisors, the latter `matching' via a certain non-holomorphic map. Suitable examples of threefolds …
Consider genus g curves that admit degree d covers to elliptic curves only branched at one point with a fixed ramification type. The locus of such covers forms a one parameter family Y that naturally maps into the moduli space of stable genus g curves Mˉg. We study the geometry of Y, and pr…
Eisenbud Popescu and Walter have constructed certain special 4-dimensional sextic hypersurfaces as Lagrangian degeneracy loci. We prove that the natural double cover of a generic EPW-sextic is a deformation of the Hilbert square of a K3-surface and that the family of such varieties is locally complete for deformations …
Study b-divisors on Kähler manifolds linking them to currents.
problem Intersection theory of b-divisors on Kähler manifolds.
method Established correspondence between closed positive currents and nef b-divisors.
result Intersection theory of nef b-divisors answered.
Study contact geometry of symplectic divisors, invariant under specific transformations.
problem Understanding contact structures on symplectic divisors and their boundaries.
method Invariant analysis of contact structures under toric and interior blow-ups/blow-downs, open book decomposition construction.
result Contact structure on divisor boundaries is invariant under specified transformations.
Abstract: Study motion of divisors on curves with topological constraints.
problem Topological restrictions on divisors' motion.
method Analysis of closed motion of simple real divisors on non-singular real algebraic projective curves.
result Found topological restrictions on divisors' motion.
Given a (smooth) complex analytic family of compact complex manifolds, we prove that the central fibre must be Moishezon if the other fibres are Moishezon. Using a "strongly Gauduchon metric" on the central fibre whose existence was proved in our previous work on limits of projective manifolds, we show that the irreduc…
In this paper, we extend the existence and regularity theorems for Kähler-Einstein metrics having conic singularities along a simple normal crossing divisor to the case of normal crossing divisor, i.e. when components of the divisor are allowed to intersect themselves transversely.
The paper extends intersection theory for b-divisors, proving monotonicity and volume inequalities.
problem Intersection theory for b-divisors and monotonicity of intersection products.
method Developed general intersection theory of nef b-divisors, defined restricted volume, proved monotonicity.
result Proved quantitative monotonicity of intersection product and new volume inequalities.
The paper proves extension theorems for holomorphic sections from divisors.
problem Extension of holomorphic sections from reduced unions of strata of divisors.
method Proves an Ohsawa--Takegoshi type extension theorem.
result Qualitative results on extension from snc divisors and generic global generation of vector bundles.
Study Lagrangian Floer theory in smooth divisor complements.
problem Intersection Floer theory of Lagrangians in smooth divisor complements.
method Complete construction of Floer homology.
result Floer homology for Lagrangians in smooth divisor complements constructed.
This paper studies Poisson structures defined by divisor ideals.
problem Understanding Poisson structures with degeneracy captured by divisor ideals.
method Developed a framework using divisor ideals and Lie algebroids.
result Effective methods for studying Poisson structures of divisor-type.
Study locates divisors in Hodge bundle with specific properties.
problem Locating effective divisors in the projectivized Hodge bundle.
method Computing the class of closures of loci of canonical divisors with specific conditions.
result Strata of canonical and bicanonical divisors with double zeros span extremal rays of pseudoeffective cones.
The paper provides a combinatorial criterion for realizing tropical pluri-canonical divisors.
problem Determining when a tropical pair corresponds to a smooth algebraic curve with a pluri-canonical divisor.
method Introducing tropical normalized covers and reducing the problem to their realizability.
result Generalizes previous work on tropical canonical divisors and incorporates recent progress on k-differentials. Solves the realizability problem for tropical canonical divisors.
problem Deciding if effective tropical canonical divisors can be realized by smooth curves.
method Using compactifications of strata of abelian differentials and combinatorial conditions.
result Provides a purely combinatorial condition to decide realizability.
Paper proves positivity for differential classes, similar to earlier work on stable curves.
problem Positivity of divisor classes for families of stable differentials.
method Establishes analogous positivity result to Cornalba-Harris for stable differentials.
result Analogous positivity result for divisor classes of stable differentials.
Solves logarithmic ∂-equation on Kähler manifolds with smooth divisors.
problem Closedness of logarithmic forms and injectivity theorems.
method Cyclic covering trick to solve ∂-equation.
result Unobstructed deformations for smooth divisors.
New effective divisors found in moduli spaces from abelian differentials.
problem Computing effective divisors in moduli spaces Mg,n. method Utilizing maps between moduli spaces and the degeneration of abelian differentials.
result Many new classes of effective divisors computed and reproduced known results.
Study shows normal distribution in divisor counts of random sections on complex manifolds.
problem Distribution of divisors on complex manifolds.
method Central limit theorem for smooth linear statistics of Gaussian sections.
result Asymptotic normality of divisor counts.
Study of zero-divisors in sedenions via determinant factorization.
problem Characterizing zero-divisors in the sedenion algebra.
method Factorization of determinant of left multiplication, reduction to quaternionic normal form, block computation.
result Quartic polynomial factorization of determinant, geometric model of zero-divisor locus.
New complete Calabi-Yau metrics found in complex space.
problem Finding metrics on complex spaces with specific conditions.
method Generalized Calabi ansatz, non-archimedean Monge-Ampère equation.
result Complete Calabi-Yau metrics constructed in Fano manifolds.
Floer theory for Lagrangians in open symplectic manifolds with smooth divisors.
problem Floer homology for Lagrangians in open symplectic manifolds with smooth divisors.
method Compactification of moduli space of pseudo-holomorphic discs, using a stronger boundary condition than stable maps.
result Established fundamental properties of the compactification as a topological space.
For homogeneous simply connected Hodge manifolds it is proved that the set of coherent vectors orthogonal to a given one is the divisor responsible for the homogeneous holomorphic line bundle of the coherent vectors. In particular, for naturally reductive spaces, the divisor is the cut locus.
Floer homology constructed for monotone Lagrangians in smooth divisor complements.
problem Computing Floer homology for Lagrangians in smooth divisor complements.
method Compactification of moduli spaces of holomorphic discs and strips, introduction of Kuranishi structures.
result RGW compactifications admit Kuranishi structures, enabling construction of Floer homology.
The study provides criteria for K-stability of Fano varieties using anticanonical Q-divisors.
problem Determining K-stability of Fano varieties.
method Applying Li and the first author's theorem, proposing and proving conditions related to anticanonical Q-divisors.
result Proposed condition sufficient for K-stability of Fano varieties, related to Berman-Gibbs stability.
The paper proves finiteness for stable Lagrangian fibrations with a given divisor.
problem Finiteness of deformation classes of hyperkähler Lagrangian fibrations.
method Survey and proof of finiteness for stable Lagrangian fibrations with a given discriminant divisor.
result Finiteness for stable Lagrangian fibrations with a given discriminant divisor.
The Miyaoka-Yau inequality is proven for certain singular varieties with big canonical or anticanonical divisors.
problem Establishing the Miyaoka-Yau inequality for singular varieties with specific divisors.
method Defining the non-pluripolar product and establishing the Bogomolov-Gieseker type inequality for Higgs sheaves; investigating second Chern class inequalities.
result Proven the Miyaoka-Yau inequality for projective klt varieties with big canonical or anticanonical divisors.
The paper classifies and studies symplectic and contact properties of circular spherical divisors.
problem Investigating symplectic and contact topology of circular spherical divisors.
method Classification and analysis of concave circular spherical divisors, including embedding, Stein fillability, and rational homology type determination.
result All concave circular spherical divisors up to toric equivalence are realized as symplectic log Calabi-Yau pairs with minimal complements.
Introduces algorithm for Weinstein handlebodies of certain divisors.
problem Constructing Weinstein handlebodies for complements of smoothed toric divisors.
method Explicit coordinates and simple example for algorithm.
result Produces Weinstein Kirby diagrams for complements of smoothed toric divisors.
Study Weinstein structures on toric divisors' complements.
problem Understanding Weinstein structures on toric divisors' complements.
method Define a partially-centered condition on Delzant polytopes, develop an algorithm for Weinstein handlebody diagrams.
result Explicit Weinstein structures for complements of smoothed toric divisors.
Recently it was shown by H. Guenancia and M. Paun that a singular metric satisfying the conical Kahler-Einstein equation with a simple normal crossing divisor is equivalent to a conical metric along that divisor. In this note, we present an alternative proof of their theorem.
The study finds infinitely many divisors in a specific space of geometric objects.
problem Understanding the effective cone of moduli spaces of abelian differentials.
method Exhibiting extremal effective divisors from abelian differential strata.
result Infinitely many extremal effective divisors discovered in Mg,n. Normal forms and moduli stacks for flat connections on complex manifolds.
problem Understanding singular flat connections on complex manifolds.
method Introducing homogeneous Lie groupoids and studying their representation theory to prove normal form theorems and moduli space structures.
result Moduli spaces of singular flat connections admit the structure of algebraic quotient stacks.
We investigate the notion of symplectic divisorial compactification for symplectic 4-manifolds with either convex or concave type boundary. This is motivated by the notion of compactifying divisors for open algebraic surfaces. We give a sufficient and necessary criterion, which is simple and also works in higher dimens…
Study projective klt pairs with nef anti-canonical divisor and their properties.
problem Characterize properties of projective klt pairs with nef anti-log canonical divisors.
method Analyze maximally rationally connected fibration and use numerical dimension analogy.
result Numerical dimension of anti-log canonical divisor on X matches that on a general fiber. The flow contracts cone divisors on Kähler surfaces to points.
problem Analyzing the conical Kähler-Ricci flow on Hirzebruch surfaces.
method Using the momentum construction of Calabi, the conical Kähler-Ricci flow is studied on Hirzebruch surfaces.
result The flow either converges to a sphere or a single point, or contracts the cone divisor to a single point.
We give a simple criterion for slope stability of Fano manifolds X along divisors or smooth subvarieties. As an application, we show that X is slope stable along an ample effective divisor D⊂X unless X is isomorphic to a projective space and D is a hyperplane section. We also give counterexamples to Au…
New insights into hyperelliptic divisors via integrable Hirota equations.
problem Understanding the geometry of hyperelliptic divisors.
method Proving the vanishing of genus 3 theta constants with even characteristics.
result Integrable Hirota equations specify the structure of hyperelliptic divisors.