New proof for curved 3-cohom manifold rational ellipticity.
problem Rational ellipticity of curved manifolds with specific cohomogeneity.
method Proved rationally elliptic for cohomogeneity-three manifolds with positive curvature and no boundary quotient.
result Closed, simply connected, positively curved, cohomogeneity-three manifolds without boundary are rationally elliptic.
Rational ellipticity proven for G-manifolds with specific quotient properties.
problem Conditions for rational ellipticity in G-manifolds. method Proving rational ellipticity based on quotient properties and manifold submetries.
result Compact, simply connected G-manifolds with certain quotient properties are rationally elliptic. Classifies rationally elliptic manifolds and proves geometric formality properties.
problem Classifying and understanding geometric formality in rationally elliptic manifolds.
method Cohomology structure analysis and geometric formality criteria.
result Geometrically formal six-dimensional manifolds with specific Betti numbers are identified.
Study shows conditions for rational ellipticity of manifolds with symmetries.
problem Conditions for rational ellipticity of manifolds with symmetries.
method Analyzes conditions on compact simply connected manifolds with G-actions. result Proves rational ellipticity of M/G if M satisfies certain conditions. We give a characterization of closed, simply connected, rationally elliptic 6-manifolds in terms of their rational cohomology rings and a partial classification of their real cohomology rings. We classify rational, real and complex homotopy types of closed, simply connected, rationally elliptic 7-manifolds. We give par…
Upper bound found for torus actions on certain manifolds.
problem Bounding torus actions on rationally elliptic manifolds.
method Classifying manifolds with maximal-rank torus actions up to equivariant rational homotopy type.
result An upper bound on torus rank for these manifolds.
The study explores geometric formality in specific dimensions of rationally elliptic manifolds.
problem Investigating geometric formality for rationally elliptic manifolds of dimensions 6 and 7.
method Analyzing real cohomology and homotopy properties to determine geometric formality.
result Geometrically formal six-dimensional biquotients with b2=3 have symmetric space cohomology. Researchers prove a complex geometric conjecture about certain manifolds.
problem Compact simply connected Riemannian manifolds with nonnegative sectional curvature.
method Assumption of entire Grauert tube and real analytic structure.
result Compact simply connected Riemannian manifolds with entire Grauert tube are rationally elliptic.
We characterise simply-connected biquotients which potentially admit metrics of holonomy G_2. We prove that there are at most three real homotopy types of rationally elliptic such manifolds---all of them being formal. In the course of this examination we classify rationally elliptic homotopy types and characterise 7-di…
In this work, it is shown that a simply-connected, rationally-elliptic torus orbifold is equivariantly rationally homotopy equivalent to the quotient of a product of spheres by an almost-free, linear torus action, where this torus has rank equal to the number of odd-dimensional spherical factors in the product. As an a…
Let M be a compact, connected and simply-connected Riemannian manifold, and suppose that G is a compact, connected Lie group acting on M by isometries. The dimension of the space of orbits is called the cohomogeneity of the action. If the direct sum of the higher homotopy groups of M, tensored with the field of rationa…
Simply-connected manifolds of positive sectional curvature M are speculated to have a rigid topological structure. In particular, they are conjectured to be rationally elliptic, i.e., all but finitely many homotopy groups are conjectured to be finite. In this article we combine positive curvature with rational ellipt…
The paper proves properties of manifolds under certain conditions.
problem Understanding properties of manifolds under specific conditions.
method Analyzing homotopy cofibrations and rational elliptic closures.
result Almost all manifolds satisfy Moore's conjecture at sufficiently large primes.
The article proves estimates on homotopy and cohomology dimensions in fibrations.
problem Estimates on dimensions of homotopy and cohomology groups in fibrations.
method Proves estimates in formal elliptic spaces and specific cases.
result Proves estimates on dimensions of homotopy and cohomology groups in fibrations.
Study eigenvalues of curvature operators to annihilate cobordism invariants.
problem Annihilating rational cobordism invariants on spin manifolds.
method Linear inequalities on curvature operator eigenvalues.
result Curvature conditions stabilize to annihilate invariants.
Let E(1)_p denote the rational elliptic surface with a single multiple fiber f_p of multiplicity p. We construct an infinite family of homologous non-isotopic symplectic tori representing the primitive class [f_p] in E(1)_p when p>1. As a consequence, we get infinitely many non-isotopic symplectic tori in the fiber cla…
The study creates symplectic Lefschetz fibrations and rational blowdowns for new 4-manifolds.
problem Creating symplectic Lefschetz fibrations and rational blowdowns for new 4-manifolds.
method Producing simply connected, minimal, symplectic Lefschetz fibrations and rationally blowing down Lefschetz fibrations with clustered nodal fibers.
result New constructions of small symplectic exotic 4-manifolds.
The study classifies manifolds that can be split into two disk bundles.
problem Understanding manifolds that can be decomposed into two disk bundles.
method Established through topological restrictions and rational ellipticity.
result Classification of manifolds up to diffeomorphism in dimensions five and six.
Study shows unbounded Pontryagin numbers on curved manifolds.
problem Understanding unbounded Pontryagin numbers on curved manifolds.
method Analyzing rational linear combinations of Pontryagin numbers and their relation to the universal elliptic genus.
result Proves existence of unbounded Pontryagin numbers on nonnegatively curved spin manifolds.
We give a systematic method to calculate some homological data from the global monodromy of a topological elliptic surface. We apply this method to the cases 1) the transcendental lattice of an extremal elliptic K3 surface, 2) the torsion part of Mordell-Weil group of a general elliptic surface, and 3) the Mordell-Weil…
An elliptic theory is constructed for operators acting in subspaces defined via odd pseudodifferential projections. Subspaces of this type arise as Calderon subspaces for first order elliptic differential operators on manifolds with boundary, or as spectral subspaces for self-adjoint elliptic differential operators of …
First time projective elliptic genera constructed for oriented manifolds.
problem Defining and proving properties of projective elliptic genera.
method Topological construction and analytic interpretation via fractional index theorem.
result Modularity properties of projective elliptic genera proven.
Harer, Kas and Kirby have conjectured that every handle decomposition of the elliptic surface E(1)2,3 requires both 1- and 3-handles. In this article, we construct a smooth 4-manifold which has the same Seiberg-Witten invariant as E(1)2,3 and admits neither 1- nor 3-handles, by using rational blow-downs and K…
Let E(1)_K denote the closed 4-manifold that is homotopy equivalent (hence homeomorphic) to the rational elliptic surface E(1) and is obtained by performing Fintushel-Stern knot surgery on E(1) using a knot K in S^3. We construct an infinite family of homologous non-isotopic symplectic tori representing a primitive hom…
Study trisections on rational elliptic surfaces to find new Zariski pairs.
problem Constructing trisections and related plane curves on rational elliptic surfaces.
method Utilized Mumford representations of semi-reduced divisors to construct trisections and plane curves.
result Existence of a family of Zariski pairs degenerating to the same conic-line arrangement.
Study properties of algebraic threefolds with specific singularities.
problem Characterize and classify algebraic threefolds with certain singularities.
method Use topological invariants, rational homology, Poincaré duality, and Lie algebras.
result Relate topological invariants to Lie algebras and representations.
We give new rational blowdown constructions of exotic CP^2#n(-CP^2) (5\leq n\leq 9) without using elliptic fibrations. We also show that our 4-manifolds admit handle decompositions without 1- and 3-handles, for 7\leq n\leq 9. A strategy for rational blowdown constructions of exotic CP^2#n(-CP^2) (1\leq n\leq 4) is also…
The study finds infinitely many special Lagrangian submanifolds in certain complex manifolds.
problem Existence of special Lagrangian submanifolds in log Calabi-Yau manifolds.
method Analyzes the existence of special Lagrangian submanifolds in log Calabi-Yau manifolds using Ricci-flat Kähler metrics.
result Proves existence of infinitely many disjoint special Lagrangian submanifolds in certain log Calabi-Yau manifolds.
Defines complex manifolds for Khovanov homology computation.
problem Constructing symplectic Khovanov homology for links.
method Moduli spaces of Hecke modifications for elliptic and rational curves.
result Explicit computations of PM(X,1,n) for rational and elliptic curves. New quotient spaces with boundaries are constructed using curvature properties.
problem Constructing quotient spaces with boundaries under curvature constraints.
method Soul construction for quotient spaces, diffeomorphism of normal bundles.
result Simply connected torus manifolds with nonnegative curvature are rationally elliptic.
Study non-negatively curved GKM orbifolds and their cohomology.
problem Characterize non-negatively curved GKM orbifolds and their cohomology.
method Analyze rational cohomology rings and isometric actions of finite groups.
result Rational cohomology rings of GKM orbifolds are isomorphic to model orbifolds.
We study the Abel-Jacobi map for bisections of a certain rational elliptic surface. As an application, we construct examples of Zariski N-plets for conic arrangements.
We show that there is a complex structure on the symplectic 4-manifold W4,k obtained from the elliptic surface E(4) by rationally blowing down k sections for 2≤k≤9. And we interpret it via Q-Gorenstein smoothing. This answers affirmatively to a question raised by R. Gompf.
Study describes Abel-Jacobi map for elliptic surfaces, refining cubic-line arrangements topology.
problem Understanding the Abel-Jacobi map on elliptic surfaces and its impact on cubic-line arrangements topology.
method Analyzes the Abel-Jacobi map and its associated rational points on elliptic surfaces, applying it to refine results on cubic-line arrangements.
result Refines the understanding of cubic-line arrangements topology using the Abel-Jacobi map.
Study finite-type solutions of elliptic sinh-Gordon equation with Durham boundary conditions.
problem Finite-type solutions of elliptic sinh-Gordon equation with Durham boundary conditions.
method Determine rationality criteria for Durham conditions and analyze spectral curve properties.
result Rationality criteria are sufficient for finite-type solutions with complementary boundary conditions.
Quantum field theory methods yield a physical interpretation of elliptic cohomology.
problem Constructing elliptic cohomology with complex coefficients.
method Using 2D quantum field theory to rigorously construct cocycles.
result Physical interpretation of the elliptic index theorem with complex coefficients.
Study real Mordell-Weil group and real lines on rational elliptic surfaces and del Pezzo surfaces.
problem Characterize the real Mordell-Weil group and real lines on rational elliptic surfaces and del Pezzo surfaces.
method Explicit description of isotopy types of real lines and presentation of MW group in mapping class group.
result Explicit formula for the action of MW group in H1(XR).
Classifies rationally 4-periodic biquotients and their cohomology.
problem Identifying rationally 4-periodic biquotients and their cohomology.
method Cohomological analysis and classification of biquotients.
result Classification of compact simply connected biquotients that are rationally 4-periodic.
New exotic 4-manifolds with even b2+ and Z/2Z fundamental group.
problem Creating new exotic smooth structures on 4-manifolds with specific fundamental groups.
method Using double node surgery and rational blowdown constructions on elliptic fibrations with a free involution.
result Construction of infinitely many irreducible exotic smooth structures.
A functional ansatz is developed which gives certain elliptic solutions of the Witten-Dijkgraaf-Verlinde-Verlinde (or WDVV) equation. This is based on the elliptic trilogarithm function introduced by Beilinson and Levin. For this to be a solution results in a number of purely algebraic conditions on the set of vectors …
In this paper we show that a simply connected 8-dimensional manifold M of positive sectional curvature and symmetry rank ≥2 resembles a rank one symmetric space in several ways. For example, the Euler characteristic of M is equal to the Euler characteristic of S^8, H P^2 or C P^4. And if M is rationally elliptic …
The paper proves properties of image structures of fibrations with semi-positive curvature.
problem Structures and images of maximal rationally connected fibrations of projective manifolds with semi-positive holomorphic sectional curvature.
method Generalizes Yang's solution using RC positivity for Yau's conjecture.
result The canonical bundle of images of such fibrations is not big.
We study algebraic solutions of the Riccati equation over the field of rational functions C(t), and over the elliptic function field C(℘,℘′).
An unobstructedness theorem is proved for deformations of compact holomorphic Poisson manifolds and applied to a class of examples. These include certain rational surfaces and Hilbert schemes of points on Poisson surfaces. We study in particular the Hilbert schemes of the projective plane and show that a generic deform…
The study constructs symplectic 4-manifolds with exotic structures.
problem Creating symplectic 4-manifolds with exotic smooth structures.
method Using star surgeries and complex singularities, the study constructs these manifolds.
result Symplectic 4-manifolds with one Seiberg-Witten basic class are constructed.
Authors prove Torelli theorem for a specific type of gravitational instantons.
problem Identifying diffeomorphism types of gravitational instantons.
method Using mirror special Lagrangian fibrations and recent work on rational elliptic surfaces.
result Identify 10 diffeomorphism types of ALHb∗ gravitational instantons. This short note presents a simple construction of nonisotopic symplectic tori representing the same primitive homology class in the symplectic 4-manifold E(1)_K, obtained by knot surgery on the rational elliptic surface E(1) with the left-handed trefoil knot K. E(1)_K has the simplest homotopy type among simply-connect…
Proves approximation and interpolation for regular immersions directed by algebraically elliptic cones.
problem Approximation and interpolation for regular immersions directed by algebraically elliptic cones.
method Uses homotopy-theoretic necessary and sufficient conditions for approximation and interpolation.
result Homotopy-theoretic conditions for approximation and interpolation are satisfied in many cases of interest.