Sharp estimates for Struwe's decomposition in various dimensions.
problem Quantifying the distance of functions to sums of Talenti bubbles.
method Developed new quantitative estimates for the distance of functions to the manifold of sums of Talenti bubbles in different dimensions.
result Sharp quantitative estimates for the distance of functions to sums of Talenti bubbles in various dimensions.
In this paper, using blow-up analysis, we prove a quantization result for an elliptic equation with critical exponential growth on compact Riemannian surface without boundary. Similar results for Euclidean space were obtained by Adimurthi-Struwe \cite{Adi-Stru}, Druet \cite{Druet}, Lamm-Robert-Struwe \cite{L-R-S}, Mart…
Harmonic map flow's singularity properties proven with Lojasiewicz inequalities.
problem Finite-time singularities of harmonic map flow in critical dimensions.
method Proving a weighted Lojasiewicz inequality.
result Continuity of body map and no-neck property for bubble-tree decompositions.
Paper proves uniqueness of weak solutions for Plateau flow.
problem Proving uniqueness of weak solutions for Plateau flow.
method Used natural energy condition and alternative methods from Struwe.
result Proves uniqueness of weak solutions under natural condition.
We give new estimates for a critical elliptic system introduced by Rivière-Struwe in \cite{riviere_struwe} (see also the work of Rupflin \cite{rupflin} and Schikorra \cite{schikorra_frames}), which generalises PDE solved by harmonic (and almost harmonic) maps from a Euclidean ball $B_1 \In \R^n$ into Riemannian manifol…
We establish that finite-time singularities do not occur in four-dimensional Yang-Mills flow, confirming the conjecture of Schlatter, Struwe, and Tahvildar-Zadeh. The proof relies on a weighted energy identity and sharp decay estimates in the neck region.
New method proves existence of constant mean curvature disks on convex surfaces.
problem Proving existence of constant mean curvature disks on convex surfaces.
method Sacks-Uhlenbeck type perturbation instead of heat flow.
result Existence for all H∈(0,H0) when Σ is convex and has mean curvature bounded below by H0. Paper explores weak solutions' regularity in critical dimensions without conservation law.
problem Regularity of weak solutions to higher order elliptic systems in critical dimensions.
method Elementary and unified treatment, without conservation law.
result Interior Hölder continuity for solutions in critical dimensions.
In this note, we study the curvature flow to Nirenberg problem on S2 with non-negative nonlinearity. This flow was introduced by Brendle and Struwe. Our result is that the Nirenberg problems has a solution provided the prescribed non-negative Gaussian curvature f has its positive part, which possesses non-degenera…
In this paper, we prove estimates and quantitative regularity results for the harmonic map flow. First, we consider H^1_loc-maps u defined on a parabolic ball P\subset M\times R and with target manifold N, that have bounded Dirichlet-energy and Struwe-energy. We define a quantitative stratification, which groups togeth…
Proves existence of planar curves with specific curvature.
problem Existence of planar closed curves with prescribed curvature.
method Variational methods, adding a parameter, monotonicity trick.
result Existence of planar closed curves with prescribed curvature for some curvature functions.
We study the limiting behaviour of solutions to abelian vortex equations when the volume of the underlying Riemann surface grows to infinity. We prove that the solutions converge smoothly away from finitely many points. The proof relies on a priori estimates for functions satisfying generalised Kazdan-Warner equations.…
We define a family of functionals generalizing the Yang-Mills functional. We study the corresponding gradient flows and prove long-time existence and convergence results for subcritical dimensions as well as a bubbling criterion for the critical dimensions. Consequently, we have an alternate proof of the convergence of…
Study sesqui-harmonic map flow from Riemannian surfaces
problem Investigate sesqui-harmonic map flow from Riemannian surfaces
method L2-gradient flow of an energy functional
result Generalizes Struwe's regularity result for harmonic maps
New heat flow for harmonic maps avoids singularities but not bubbles.
problem Finite time singularities in harmonic maps.
method Introduces a conformal heat flow for harmonic maps defined by an evolution equation.
result Global weak solution exists, smooth except at most finitely many points.
Study proves existence of non-trivial harmonic map flows to hemispheres.
problem Existence of non-trivial harmonic map flows to hemispheres.
method Construction of infinitely many weak solutions to harmonic map flow starting from non-minimizing but stationary maps.
result Proves existence of non-trivial self-expanding harmonic map flows to hemispheres.
The goal of the present work is twofold. First we prove the existence of an Hilbert Manifold structure on the space of immersed oriented closed surfaces with three derivatives in L2 in an arbitrary sub-manifold Mm of an euclidian space RQ. Second, using this Hilbert manifold structure, we prove a lower semi co…
We relate the existence problem of harmonic maps into S2 to the convex geometry of S2. On one hand, this allows us to construct new examples of harmonic maps of degree 0 from compact surfaces of arbitrary genus into S2. On the other hand, we produce new example of regions that do not contain closed geodesics (…
Study on curvature flow in 4D ball, proving existence and convergence.
problem Existence of metrics with prescribed T-curvature on the 4D unit ball. method Using T-curvature flow and Morse-theoretic approach, combining Ache-Chang's inequality. result Existence results and exponential convergence to extremal metric.
Study heat flow for half-harmonic maps and harmonic maps with free boundary.
problem Integrability and regularity of half-harmonic maps and harmonic maps with free boundary.
method Introduced a heat flow associated to half-harmonic maps and constructed weak solutions via Ginzburg-Landau approximation.
result Proved partial regularity of weak solutions in space and time.
Study describes how conformal metrics behave as Q-curvature changes, forming spherical bubbles.
problem Understanding the asymptotic behavior of conformal metrics with null Q-curvature.
method Analyzes the GJMS operator and uses higher order Bol's inequality to describe the metrics' behavior.
result Normalized conformal metrics form exactly one spherical bubble as λ approaches zero.
The study proves no smooth solutions for certain conformally invariant equations.
problem Proving the non-existence of smooth solutions for specific conformally invariant equations.
method Analyzing polynomially cone conditions and using Liouville-type theorems.
result No non-constant polynomial solutions exist for the given equation.
We introduce a flow of maps from a compact surface of arbitrary genus to an arbitrary Riemannian manifold which has elements in common with both the harmonic map flow and the mean curvature flow, but is more effective at finding minimal surfaces. In the genus 0 case, our flow is just the harmonic map flow, and it tries…
The paper solves curvature prescription on a disk with negative Gaussian curvature.
problem Prescribing Gaussian curvature and geodesic curvature on a disk with negative Gaussian curvature.
method Variational approach, critical points of a functional, perturbation argument, monotonicity trick, blow-up analysis, Morse index estimates.
result General existence results for the curvature prescription problem.
The paper constructs new non-trivial harmonic maps into higher-dimensional target manifolds.
problem Existence of non-trivial harmonic maps into higher-dimensional target manifolds.
method Perturbative argument, refined neck-analysis, energy identity, min-max problems.
result Construction of an infinite family of new null-homotopic n-harmonic n-spheres. The paper proves the existence of constant mean curvature disks with capillary boundary conditions.
problem Existence of constant mean curvature disks with specific boundary conditions.
method Extending Struwe's result to a broader range of boundary angles.
result Existence of constant mean curvature disks with index at most 1.
Normal solutions found for a specific curvature equation in 4D space.
problem Blow-up behavior in the Nirenberg problem and prescribed Q-curvature equation in R^4.
method Analyzing the integral form of solutions and proving existence and non-existence results.
result Normal solutions exist if and only if p ∈ (0, 4) and a specific range for Λ.
Abstract theory of flows of geometric structures on manifolds.
problem Deformations and flows of geometric structures on manifolds.
method Develops an abstract theory using infinitesimal action of GL(n,R) and bundle decompositions.
result Almost monotonicity formula for harmonic flow of H-structures, leading to regularity and energy gap results.
Study of metrics with prescribed curvature and geodesic curvature on a disc.
problem Existence and behavior of conformal metrics with prescribed curvature and boundary geodesic curvature.
method Variational characterization and gradient flow approach.
result Existence of solutions or blow-up to a spherical cap, leading to existence results via shadow flow.
We construct finite time blow-up solutions to the 3-dimensional harmonic map flow into the sphere S2, \begin{align*} u_t & = Δu + |\nabla u|^2 u \quad \text{in } Ω\times(0,T) \\ u &= u_b \quad \text{on } \partial Ω\times(0,T) \\ u(\cdot,0) &= u_0 \quad \text{in } Ω, \end{align*} with $u(x,t): \bar Ω\times [0,T) \to …
The problem of prescribing Gaussian curvature on Riemann surface with conical singularity is considered. Let (Σ,β) be a closed Riemann surface with a divisor β, and Kλ=K+λ, where K:Σ→R is a Hölder continuous function satisfying maxΣK=0, K≡0, and λ∈R. If the Eule…
Researchers describe and compare decompositions of Poincaré duality pairs.
problem Understanding and comparing different decompositions of Poincaré duality pairs.
method Developed and described edge splittings of decompositions based on group properties.
result Compared decompositions with two other related decompositions.
The paper proposes and discusses semiorthogonal decompositions for moduli spaces of vector bundles.
problem Decompositions of moduli spaces of vector bundles with fixed determinant of odd degree.
method Semiorthogonal decompositions, Grothendieck ring of varieties, mirror symmetry, graph potentials, Fukaya category.
result Evidence for a conjectural semiorthogonal decomposition of moduli spaces of rank 2 bundles with odd determinant.
The paper classifies decompositions of 3-sphere and lens spaces with handlebodies.
problem Classifying decompositions of 3-manifolds with handlebodies.
method Studied decompositions of 3-sphere and lens spaces with three handlebodies, using stabilizations.
result Determined whether decompositions are stabilized.
We combine aspects of the notions of finite decomposition complexity and asymptotic property C into a notion that we call finite APC-decomposition complexity. Any space with finite decomposition complexity has finite APC-decomposition complexity and any space with asymptotic property C has finite APC-decomposition comp…
This paper generalizes octahedral decomposition to links in thickened surfaces.
problem Understanding the geometry of links in thickened surfaces.
method Octahedral decomposition of links in thickened surfaces.
result Nonpositive curvature of the complement and essential-ness of edges proved.
Researchers compute Goeritz groups for all (1,1)-link decompositions.
problem Computing Goeritz groups for all (1,1)-link decompositions.
method Analyzing surface decompositions and isotopy classes of homeomorphisms.
result Computed Goeritz groups for all (1,1)-link decompositions.
This paper studies the convergence of penalized energy to harmonic maps in Riemannian manifolds.
problem Analyzing the convergence of penalized energy to harmonic maps in Riemannian manifolds.
method Using the penalized energy functional and weak convergence techniques, the paper proves the energy identity for Ginzburg-Landau approximation of harmonic maps.
result The defect measure ν can be expressed as the sum of energies of harmonic spheres for arbitrary manifolds.
Study concordance of decompositions from defining sequences in 3-sphere.
problem Understanding concordance and bordism of decompositions from defining sequences.
method Relate to invariants of toroidal decompositions and cobordism of homology manifolds.
result At least uncountably many concordance classes of decompositions in 3-sphere.
Given a Delaunay decomposition of a compact hyperbolic surface, one may record the topological data of the decomposition, together with the intersection angles between the `empty disks' circumscribing the regions of the decomposition. The main result of this paper is a characterization of when a given topological decom…
Study shows OAT decomposition generates unexplained profit and loss, while SU decompositions depend on risk factor order.
problem Understanding profit and loss attribution in financial markets.
method Used financial market data from 2003 to 2022 to compare OAT, SU, and ASU decompositions.
result SU decompositions are sensitive to risk factor order and cannot identify all relevant risk factors.
A new algorithm speeds up CP decomposition for large tensors.
problem Efficiently processing large-scale tensors in real-time.
method Randomized online CP decomposition (ROCP) algorithm.
result ROCP reduces computing time and memory usage significantly.
Paper characterizes optimization landscape of Tucker decomposition.
problem Finding exact Tucker decomposition is a nonconvex optimization problem.
method Characterized the optimization landscape and provided a local search algorithm.
result All local minima are globally optimal if tensor has an exact Tucker decomposition.
A double pants decomposition of a 2-dimensional surface is a collection of two pants decomposition of this surface introduced in arXiv:1005.0073v2. There are two natural operations acting on double pants decompositions: flips and handle twists. It is shown in arXiv:1005.0073v2 that the groupoid generated by flips and h…
Smooth 4-manifolds have simple horizontal decompositions.
problem Classifying smooth, closed, orientable 4-manifolds.
method Horizontal handlebody decomposition.
result Simplest horizontal decompositions classify closed 4-manifolds.
Let J1 be the real form of a complex simple Jordan algebra such that the automorphism group is F4(−20). By using some orbit types of F4(−20) on J1, for F4(−20), explicitly, we give the Iwasawa decomposition, the Oshima--Sekiguchi's Kε−Iwasawa decomp…
We study the topological types of pants decompositions of a surface by associating to any pants decomposition P, in a natural way its pants decomposition graph, Γ(P). This perspective provides a convenient way to analyze the maximum distance in the pants complex of any pants decomposition to a pants decomposition c…
New method uses random decompositions for high-dimensional Bayesian optimization.
problem Learning accurate decompositions for high-dimensional black-box functions.
method Data-independent random tree-based decomposition sampling.
result Random decomposition upper-confidence bound algorithm (RDUCB) yields significant empirical gains.