The paper proves properties of branched covers of specific knots and tori.
problem Investigating the smoothness and diffeomorphism of specific 4-manifolds.
method Analyzing double branched covers of twist-roll spun knots and turned twisted tori, applying techniques to show diffeomorphism.
result Proves that certain 4-manifolds are diffeomorphic to standard manifolds.
Extends exotic embeddings of RP^2 to a larger family and produces homotopy spheres.
problem Constructing exotic embeddings of RP^2 and homotopy spheres.
method Using Montesinos knots and roll-spun knots to prove the existence of homotopy spheres.
result An infinite family of homotopy spheres and homotopy CP^2s are produced.
Paper extends Miyazawa's construction to more 4-manifolds, finding exotic involutions and embeddings.
problem Finding exotic involutions and embeddings in 4-manifolds.
method Real Seiberg-Witten theory.
result Many infinite families of exotic involutions and embeddings.
A complex projective tower or simply a CP-tower is an iterated complex projective fibrations starting from a point. In this paper we classify all 6-dimensional CP-towers up to diffeomorphism, and as a consequence, we show that all such manifolds are cohomologically rigid, i.e., they are completely d…
Proves a specific knot is not smoothly slice using real invariants.
problem Determining the smooth sliceness of (2n,1)-cables of the figure-eight knot. method Used real Seiberg-Witten Frøyshov invariant and developed an equivariant lattice homotopy type.
result Proves the (2n,1)-cable of the figure-eight knot is not smoothly slice when n is odd. Study extends gauge-theoretic invariant to higher-dimensional Kahler surfaces and calculates homotopy groups.
problem Calculate higher homotopy groups of symplectic mapping spaces on modified Kahler surfaces.
method Apply deformation of complex objects and gauge-theoretic techniques to closed Kahler surfaces.
result Show that even-dimensional higher homotopy groups of symplectic mapping spaces are infinitely generated.
The Farey tree helps embed rational balls and lens spaces into complex projective space.
problem Embedding rational homology balls and lens spaces into complex projective space.
method Recursive Kirby calculus argument using the Farey tree.
result Explicit constructions of embeddings of triples of rational homology balls into homotopy CP2. Study rules out exotic S4 and #nCP2 construction using zero surgery homeomorphisms.
problem Tackles the possibility of constructing exotic S4 or #nCP2 using zero surgery homeomorphisms. method Uses zero surgery homeomorphisms to relate slice properties of knots stably after a connected sum with a 4-manifold.
result Rules out the possibility of constructing exotic S4 or #nCP2 using zero surgery homeomorphisms. 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.
We show that the manifold *CP^2 # *RP^4, which is homotopy equivalent but not homeomorphic to CP^2 # RP^4, is in fact smoothable.
The paper studies almost complex torus manifolds using graphs and Hirzebruch genera, proving properties of their fixed points and cohomology.
problem Understanding the fixed points and cohomology of almost complex torus manifolds.
method Using directed labeled multigraphs and Hirzebruch genera to encode and analyze the manifolds.
result Almost complex torus manifolds have positive Todd genus and at least n+1 fixed points.
Floer homotopy theory applies to Lagrangians, overcoming curvature issues.
problem Curvature phenomena in high dimensions for monotone Lagrangians.
method Introduces N-truncated, R-oriented flow categories and module prospectrum. result Well-defined invariants for closed embedded monotone Lagrangians.
The paper classifies certain 13-dimensional manifolds up to various equivalences.
problem Classifying certain 13-dimensional manifolds up to diffeomorphism, homeomorphism, and homotopy equivalence.
method Analyzing cohomology rings and proving existence of metrics of non-negative sectional curvature.
result Certain 13-dimensional manifolds are classified up to various equivalences.
We extend the Kamada-Miyazawa polynomial to virtual singular links, which is valued in Z[A2,A−2,h]. The decomposition of the resulting polynomial into two components, one in Z[A2,A−2] and the other in Z[A2,A−2]h yields the decomposition of the Kauffman-Jones polynomial o…
Classifies certain high-dimensional manifolds with specific cohomology properties.
problem Classifying smooth manifolds with a specific cohomology structure.
method Analyzes cohomology rings and uses topological equivalences.
result Classifies manifolds up to diffeomorphism, homeomorphism, and homotopy equivalence.
Totally real immersions f of a closed real surface Σ in an almost complex surface M are completely classified, up to homotopy through totally real immersions, by suitably defined homotopy classes M(f) of mappings from Σ into a specific real 5-manifold E(M), while M(f) themselves are subject …
The paper explores the genus of surfaces in complex projective spaces and improves minimal genus bounds.
problem Investigating the genus of surfaces in complex projective spaces.
method Analyzing knots and torus knots in CP2 and CP2#CP2. result The CP2-genus of knots is unbounded, unlike its topological counterpart. In this short note we show that the existence of bilaterally symmetric extremal Kähler metrics on CP2♯2CP2ˉ.
We construct potentially new manifolds homeomorphic but not diffeomorphic to CP2#8CP2 and CP2#9CP2 via rational blowdown surgery along certain 4-valent plumbing graphs. This way all the graph classes from \cite{weighted} have a represen…
The set of maximal non-integrable structures (SU(2)×SU(2),B,I), where B is Killing-Cartan metric is described as subset of CP3. The visualization of complex projective space CP3 as tetrahedron which edges and faces are CP1 and CP2 is used.
Study on slicing knots in 4-manifolds, focusing on CP^2-slicing numbers.
problem Understanding the slicing properties of knots in 4-manifolds.
method Lower and upper bounds on CP^2-slicing numbers using double branched covers and Seifert forms.
result Findings on the finite and distinct CP^2-slicing numbers for certain knots.
We study smooth isotopy classes of complex curves in complex surfaces from the perspective of the theory of bridge trisections, with a special focus on curves in CP2 and CP1×CP1. We are especially interested in bridge trisections and trisections that are as simple as possible, whi…
Little is known about the global topology of the Fatou set U(f) for holomorphic endomorphisms f:CPk→CPk, when k>1. Classical theory describes U(f) as the complement in CPk of the support of a dynamically-defined closed positive (1,1) current. Given any closed positive $(…
We consider the non-trivial Ricci soliton on CP2#CP2 constructed by Koiso and Cao. It is a Kähler metric invariant by the U(2) action on CP2#CP2. We study its Yamabe equation and prove it has exactly one U(2)−invariant solution up to homothecies.
New complex structure on hyperbolic disc within hyperkaehler space.
problem Complex structure on hyperbolic disc within hyperkaehler space.
method Mostow decomposition and complex adjoint orbit analysis.
result Complex structure on hyperbolic disc differs from natural embedding.
Revisits Koiso's rigid metrics on complex projective spaces.
problem Computing obstructions to integrability of deformations.
method Elementary complex differential geometry.
result Computes Koiso's obstruction on CPnimesCP1. We introduce the 2-nodal spherical deformation of certain singular fibers of genus 2 fibrations, and use such deformations to construct various examples of simply connected minimal symplectic 4-manifolds with small topology. More specifically, we construct new exotic minimal symplectic 4-manifolds homeomorphic …
6D symplectic manifold with many homologous but inequivalent submanifolds.
problem Finding many symplectic submanifolds in a 6D manifold.
method Hyperelliptic Lefschetz fibrations on 4-manifolds.
result Infinitely many mutually homologous but homotopy inequivalent submanifolds.
The paper shows links with 2 components are not smoothly slice in a specific 4-manifold.
problem Tackles the smooth sliceness of 2-component links in a specific 4-manifold.
method Uses classical topological and smooth obstructions, along with constructive arguments exploiting symmetries.
result Demonstrates the existence of infinitely many integer homology 3-spheres with specific properties.
In this paper by reduction we construct a family of conformally flat Hamiltonian-minimal Lagrangian tori in CP3 as the image of the composition of the Hopf map H:S7→CP3 and a map ψ:R3→S7 with certain conditions.
We describe a framework for constructing the Ricci-flat metrics on the total space of the canonical bundle over CP2#CP2 (the del Pezzo surface of rank one). We construct explicitly the first-order deformation of the so-called `orthotoric metric' on this manifold. We also show that th…
In this article, we show the existence of a nontrivial Riemann surface lamination embedded in CP2 by using Donaldson's construction of asymptotically holomorphic submanifolds. Further, the lamination we obtain has the property that each leaf is a totally geodesic submanifold of CP2 with respect…
A new method for predicting with confidence for complex models.
problem Lack of reliable confidence in high-stake decision-making models.
method Developed a full-CP for sparse high-order interaction model using homotopy mining.
result SHIM achieves comparable accuracy to complex models and superior statistical power.
Hexagonal diagrams link complex curves in CP2 to minimal genus surfaces.
problem Understanding the relationship between complex curves and surfaces in CP2. method Hexagonal lattice diagrams and trisection of CP2. result Positive genus surfaces in CP2 are isotopic to complex curves if they admit hexagonal lattice diagrams. Constructs a simplicial cell decomposition of complex projective space for n ≥ 2.
problem Finding a simplicial cell decomposition for complex projective space.
method Starting with a standard crystallisation of the 2-sphere, constructing a simplicial subdivision, and quotienting by the Sym(n) action.
result Explicit construction of a simplicial cell decomposition of complex projective space for n ≥ 2.
Let M be a closed 4-manifold with π2(M)≅Z. Then M is homotopy equivalent to either CP2, or the total space of an orbifold bundle with general fibre S2 over a 2-orbifold B, or the total space of an RP2-bundle over an aspherical surface. If π=π1(M)=1 there are at most two such bundle spaces…
Consider a dihedral cover f:Y→X with X and Y four-manifolds and f branched along an oriented surface embedded in X with isolated cone singularities. We prove that only a slice knot can arise as the unique singularity on an irregular dihedral cover f:Y→S4 if Y is homotopy equivalent to $\mathbb{CP…
We present a general numerical method for investigating prescribed Ricci curvature problems on toric Kähler manifolds. This method is applied to two generalisations of Einstein metrics, namely Ricci solitons and quasi-Einstein metrics. We begin by recovering the Koiso--Cao soliton and the Lü--Page--Pope quasi-Einstein …
Defines and analyzes L2 norms on Higgs bundles over CP1.
problem Analyzing L2 norms on Higgs bundles with singularities. method Defines and analyzes a specific L2 norm on the moduli space of Higgs bundles over CP1 with certain singularities. result Proves that a limit of the defined metrics corresponds to the regulated L2 norm from Fredrickson-Neitzke's work. The study explores holomorphic Legendrian curves and superminimal surfaces in complex projective and sphere spaces.
problem Characterizing and embedding holomorphic Legendrian curves and superminimal surfaces.
method Runge approximation theorem, bijective correspondence via twistor projection, finite genus analysis.
result Every open Riemann surface embeds into CP3 as a complete holomorphic Legendrian curve. The paper embeds 4-manifolds into CP^2 x CP^1 using Lefschetz fibrations.
problem Embedding 4-manifolds into CP^2 x CP^1.
method Proving Lefschetz fibration embeddings of 4-manifolds into CP^2 x CP^1.
result Every closed, connected, orientable 4-manifold admits a smooth Lefschetz fibration embedding into CP^2 x CP^1.
Zoll manifolds with entire Grauert tubes are proven to be standard complex projective spaces.
problem Characterizing Zoll manifolds with entire Grauert tubes.
method Isometric comparison to CPn with the canonical metric. result Zoll manifolds of type CPn with entire Grauert tubes are isometric to CPn. In this paper, we first prove that any closed simply connected 4-manifold that admits a decomposition into two disk bundles of rank greater than 1 is diffeomorphic to one of the standard elliptic 4-manifolds: S4, CP2, S2×S2, or CP2#±CP2. As an…
Study transverse J-holomorphic curves linking nearly Kähler CP3 to minimal surfaces.
problem Understanding J-holomorphic curves in nearly Kähler CP3. method Introducing transverse J-holomorphic curves and establishing Bonnet-type theorems. result Classification of flat tori and construction of moment-type maps.
In this paper, first we consider the existence and non-existence of Einstein metrics on the topological 4-manifolds $3\mathbb{CP}^2 # k \bar{\mathbb{CP}}^2$ (for k∈11,13,14,15,16,17,18) by using the idea of Răsdeaconu and Şuvaina (2009) and the constructions in Park, Park, and Shin (arXiv:0906.5195v2) and…
As an application of the method of [4], we find the metric and connection on the space of conics in CP2 determined as the solution space of the ODE eqn(1). These calculations underpin the twistor construction of the Radon transform on conics in CP2 described in [5]. Two further examples of the m…
We extend the definition of Khovanov-Lee homology to links in connected sums of S1×S2's, and construct a Rasmussen-type invariant for null-homologous links in these manifolds. For certain links in S1×S2, we compute the invariant by reinterpreting it in terms of Hochschild homology. As applications…
We describe topologically the discriminant locus of a smooth cubic surface in the complex projective space CP3 that contains 5 fibres of the projection CP3⟶S4.