This paper generalizes wrinkling techniques to Haefliger structures, linking them to foliations.
problem Proving h-principles for partial differential relations with controlled singularities.
method Generalizing wrinkled embeddings to Haefliger structures and interpreting them as holonomic approximations.
result Haefliger structures provide a framework for making general wrinkling statements and imply connectivity results.
The paper connects fluid mechanics, elasticity, and geometry to study wrinkled solutions.
problem Existence of wrinkled solutions in nonlinear partial differential equations.
method Develops connections between fluids, elasticity, and isometric embeddings, mapping mechanical equations into geometric frameworks.
result Geometric theory provides a method for addressing admissibility criteria in nonlinear conservation laws.
New Poisson and near-symplectic structures found on 6D wrinkled fibrations.
problem Finding compatible geometric structures on 6D wrinkled fibrations.
method Extending wrinkled fibrations to 6D and proving the existence of rank-2 Poisson structures and near-symplectic structures.
result 6D wrinkled fibrations can be equipped with Poisson and near-symplectic structures.
Local formulas for Poisson structures on wrinkled fibrations are derived.
problem Understanding Poisson structures on specific geometric fibrations.
method Local formulæ for Poisson bivectors and symplectic forms on wrinkled fibrations.
result Local formulas for Poisson structures on wrinkled fibrations are derived.
Wrinkles form on a thin sheet bonded to a sphere, revealing energy and length scale behaviors.
problem Understanding the wrinkle formation on a thin sheet bonded to a sphere.
method Analyzing the energy of the system with the sheet's thickness as a small parameter, determining leading and next-order behaviors.
result The wrinkling pattern varies with radius, with the number of wrinkles being approximately integer multiples of the sheet thickness.
Paper generalizes wrinkled embedding concept to jet spaces.
problem Approximating homotopies of embeddings with singularities.
method Defines wrinkled embeddings for differential information in jet spaces.
result Holonomic approximation theorem holds for multi-valued sections with simple singularities.
We study simple wrinkled fibrations, a variation of the simplified purely wrinkled fibrations introduced by Williams, and their combinatorial description in terms of surface diagrams. We show that simple wrinkled fibrations induce handle decompositions on their total spaces which are very similar to those obtained from…
A {\it wrinkled embedding} f:Vn→Wm is a topological embedding which is a smooth embedding everywhere on V except a set of (n−1)-dimensional spheres, where f has cuspidal corners. In this paper we prove that any rotation of the tangent plane field TV⊂TW of a {\it smoothly embedded} submanifold $V\s…
We use the wrinkling theorem proven in Y. Eliashberg and N. Mishachev, "Wrinkling of smooth mappings and its applications - I", Invent. Math., 130(1997), 345-369, to fully describe the homotopy type of the space of S-immersions, i.e. equidimensional folded maps with prescribed folds.
Novel defects in hyperbolic sheets explain complex wrinkling patterns in nature.
problem Understanding complex wrinkling patterns in thin elastic hyperbolic surfaces.
method Non-Euclidean plate theory and investigation of branch points.
result Branch points are natural defects in hyperbolic sheets, influencing their morphology robustly.
Complex wrinkling patterns emerge in non-Euclidean elastic sheets due to energy minimization.
problem Understanding hierarchical buckling patterns in non-Euclidean elastic sheets.
method Minimizing elastic energy to explain complex wrinkling patterns.
result Branch-point singularities are key to generating complex wrinkling patterns.
An R_2-move is a homotopy of wrinkled fibrations which deforms images of indefinite fold singularities like Reidemeister move of type II. Variants of this move are contained in several important deformations of wrinkled fibrations, flip and slip for example. In this paper, we first investigate how monodromies are chang…
A knot type is exchange reducible if an arbitrary closed n-braid representative can be changed to a closed braid of minimum braid index by a finite sequence of braid isotopies, exchange moves and +/- destabilizations. In the manuscript [J Birman and NC Wrinkle, On transversally simple knots, preprint (1999)] a transver…
According to Kiyoshi Igusa a generalized Morse function on an n-dimensional manifold M is a smooth function with only Morse and birth-death singularities and a framed function is a generalized Morse function with an additional structure: a framing of the negative eigenspace at each critical point of the function f. In …
Motivated by the programmes initiated by Taubes and Perutz, we study the geometry of near-symplectic 4-manifolds, i.e., manifolds equipped with a closed 2-form which is symplectic outside a union of embedded 1-dimensional submanifolds, and broken Lefschetz fibrations on them. We present a set of four moves which allow …
We give a new proof of Markov's classical theorem relating any two closed braid representations of the same knot or link. The proof is based upon ideas in a forthcoming paper by the authors, "Stabilization in the braid groups". The new proof of the classical Markov theorem is used by Nancy Wrinkle in her forthcoming ma…
The edge of torn elastic sheets and growing leaves often form a hierarchical buckling pattern. Within non-Euclidean plate theory this complex morphology can be understood as low bending energy isometric immersions of hyperbolic Riemannian metrics. With this motivation we study the isometric immersion problem in strip a…
Paper develops a framework for hyperbolic Monge-Ampère equation on strips, proving well-posedness and stability.
problem Addressing the rigidity-flexibility dichotomy for wrinkled patterns in thin elastic sheets.
method Develops hodograph transformation and parametrix-corrector decomposition to handle corner singularities and prove well-posedness.
result Proves existence and uniqueness of hodograph weak solutions and derives energy estimates for stability.
Shells resist three out of six possible loads if simply connected.
problem Understanding the load resistance of shells.
method Formal mathematical analysis of shell strains and deflections.
result The space of strains is three-dimensional for simply-connected shells.
The paper recovers contact forms from boundary data using vector fields and Lyapunov functions.
problem Recovering contact forms from boundary data.
method Using vector fields and Lyapunov functions, the paper describes boundary data and proves reconstruction of (X,β) up to diffeomorphism. result Boundary data allow for the reconstruction of (X,β) up to a diffeomorphism of X. Unified facial behavior analysis network improves performance across tasks.
problem Independent study of facial behavior tasks.
method Single multi-task, multi-domain, multi-label network (FaceBehaviorNet).
result Joint training of facial behavior tasks yields better performance.
Estimates yearly improvement rates for nearly all technologies using US patent data.
problem Providing a comprehensive account of technological change rates.
method Mapping patents to technology domains, calculating average centrality, and estimating improvement rates.
result Variation in improvement rates from 1.9% to 228.8% per year, with software-based domains often the fastest.
New ancient compact solutions found for Yamabe flow.
problem Finding compact solutions to the Yamabe flow.
method Constructed rotationally symmetric ancient compact solutions.
result Found type I ancient compact solutions converging to self-similar solutions.
The paper examines partial regularity of Lipschitz solutions to minimal surface system.
problem Understanding the regularity of solutions to the minimal surface system.
method Investigation of stationary, integral weak, and viscosity solutions; interior gradient estimate using maximum principle.
result Partial regularity results for Lipschitz solutions, including interior gradient estimate.
Unique ancient solutions found for anisotropic curve shortening flow.
problem Finding unique solutions for anisotropic curve shortening flow.
method Constructing translating and ancient solutions under given conditions.
result Unique ancient and translating solutions found for anisotropic curve shortening flow.
The paper constructs solutions to a critical Dirac equation on spheres.
problem Solving the critical Dirac equation on spheres with singularities.
method Constructing Delaunay-type solutions and another kind of singular solutions.
result The constructed solutions are building blocks for singular solutions on Spin manifolds.
Paper classifies ancient solutions to 3D Ricci flow.
problem Classifying ancient solutions to 3D Ricci flow.
method Proves uniqueness of solutions based on classification criteria.
result Ancient solutions are either shrinking spheres or Perelman's Type II solutions.
Ancient solutions of Yamabe flow equation studied with specific parameters and properties derived.
problem Existence and properties of ancient solutions of the Yamabe flow equation.
method Construction and analysis of ancient solutions with specific parameters, derivation of properties including exact decay rate.
result Various properties of ancient solutions derived, including exact decay rate and singular limit solutions.
The paper finds solutions to Kapustin-Witten equations with singular imaginary parts.
problem Finding solutions to Kapustin-Witten equations with specific properties.
method Solving a system of non-linear ODEs to find rotationally invariant solutions.
result Explicit solutions found, including decaying rational solutions and singular imaginary parts.
Geometrically constructs solutions to 11D supergravity.
problem Finding supersymmetric solutions to 11D supergravity.
method Warped product manifolds with non-vanishing flux.
result Explicit 5-parameter moduli space of solutions.
New findings on κ-solutions with round cylinder as asymptotic shrinker.
problem Characterizing κ-solutions with specific asymptotic behavior. method Analysis of Ricci flow in dimensions n≥4. result Uniformly Positive Isoperimetric Constant (PIC) for κ-solutions. Ancient solutions of Ricci flow with Type I growth are classified.
problem Understanding ancient solutions of Ricci flow with specific curvature growth.
method Analyzing ancient solutions with Type I curvature growth in arbitrary dimensions.
result Ancient solutions with Type I growth are classified into specific types.
Study higher-dimensional Ricci flow solutions, proving uniqueness.
problem Classifying ancient solutions to the Ricci flow on Sn. method Extending [13] to higher dimensions, proving uniqueness.
result Ancient solutions are either shrinking spheres or Type II solutions.
We construct low regularity solutions of the vacuum Einstein constraint equations. In particular, on 3-manifolds we obtain solutions with metrics in $H^s\loc$ with s>23. The theory of maximal asymptotically Euclidean solutions of the constraint equations descends completely the low regularity setting. Moreove…
Researchers find entire solutions to magnetic Ginzburg-Landau equations in 4D.
problem Finding entire solutions to magnetic Ginzburg-Landau equations in 4D.
method Using Lyapunov-Schmidt reduction.
result Existence of entire solutions and saddle type solutions with specific zero sets.
New ancient solutions found for curvature flow in 2D.
problem Ancient solutions for curvature flow in 2D.
method Constructing and classifying convex ancient solutions.
result All convex ancient solutions classified for α∈(32,1). The study approximates nearly optimal Lasso solutions using convex hulls.
problem Finding diverse yet nearly optimal Lasso solutions.
method Formulate problem as approximating nearly optimal solutions with a convex hull of sampled extreme points. Use a greedy algorithm to select a small number of points.
result The proposed algorithm can approximate the solution set well and obtain diverse Lasso solutions.
This paper proves a bound on the energy of Nahm pole solutions on S3imesR+.
problem Bounding the energy of Nahm pole solutions on a specific manifold.
method Proving an energy bound using the Kapustin-Witten equation with Nahm pole boundary conditions.
result There exists a constant C>0 such that ∥FA∥L2≤C for any Nahm pole solution (A,φ). Study finds solutions for degenerate affine curve shortening flow.
problem Analyzing degenerate affine curve shortening flow.
method Solved equations for affine self-similar solutions.
result New special solutions discovered for affine curve shortening flow.
We construct new ancient compact solutions to the Yamabe flow. Our solutions are rotationally symmetric and converge, as t→−∞, to two self-similar complete non-compact solutions to the Yamabe flow moving in opposite directions. They are type I ancient solutions.
Minimax solutions are weak solutions to Cauchy problems involving Hamilton--Jacobi equations, constructed from generating families quadratic at infinity of their geometric solutions. We give a complete description of minimax solutions and we classify their generic singularities of codimension not greater than 2.
Paper shows how solutions to Allen-Cahn converge to multiphase mean curvature flow.
problem Convergence of Allen-Cahn solutions to multiphase mean curvature flow.
method Conditional convergence result of Allen-Cahn solutions to De Giorgi type BV-solutions of multiphase mean curvature flow.
result De Giorgi type BV-solutions are unique in a weak-strong sense.
Estimates moduli of continuity for viscosity solutions on manifolds.
problem Estimating moduli of continuity for viscosity solutions on manifolds.
method Extending previous work on regular solutions and viscosity solutions in Euclidean spaces.
result Established estimates of modulus of continuity for viscosity solutions of nonlinear evolution equations on manifolds.
Generic level sets in mean curvature flow are BV solutions.
problem Understanding the behavior of level sets in mean curvature flow.
method Using the framework of sets of finite perimeter and distributional solutions, the paper extends Evans and Spruck's work.
result Generic level sets are distributional solutions with optimal energy dissipation rate.
The paper concerns singular solutions of nonlinear elliptic equations, which include removable singularities for viscosity solutions, a strengthening of the Hopf Lemma including parabolic equations, Strong maximum principle and Hopf Lemma for viscosity solutions including also parabolic equations.
Real analytic solutions found for special Lagrangian equation.
problem Analyzing convex solutions of the special Lagrangian equation.
method Interior regularity established for convex viscosity solutions.
result All convex solutions are real analytic in the interior.
Proves existence and uniqueness of viscosity solutions to complex Hessian equations on compact Hermitian manifolds.
problem Existence and uniqueness of viscosity solutions to complex Hessian equations.
method Proves existence and uniqueness using viscosity solutions and determinant domination conditions.
result Viscosity solutions exist and are unique under certain conditions.
Paper shows no eternal solutions for certain flows.
problem Existence of eternal solutions for Lagrangian mean curvature flow.
method Derived mean curvature estimate for eternal solutions.
result Non-existence of eternal solutions for almost-calibrated Lagrangian mean curvature flow.