Quaternionic Monge-Ampère equations

The main result of this article is the existence and uniqueness of the solution of the Dirichlet problem for quaternionic Monge-Ampère equations in quaternionic strictly pseudoconvex bounded domains in ℍ ⁿ . We continue the study of the theory of plurisubharmonic functions of quaternionic variables started by the author at [2].     

Isolated singularities of Monge-Ampère equations

Letz=z(x, y) be a real-valued twice continuously differentiable solution of the elliptic Monge-Ampère equationAr+2Bs+Ct+rt – s ²=E in the punctured disk 0<(x–x ₀)²+(y–y ₀)²<². Assume thatq is continuous at (x₀, y₀). Our aim is to give sufficient conditions on the coefficientsA,..., E which ensure that the singularity (x ₀,y ₀) is removable. This generalizes an earlier result of Jörgens (Math. Ann. 129 (1955), 330–344).     

拋物型Monge-Ampère方程

<正>这篇文章研究的是方程 H_r+2K_s+L_t+N(rt-s~2)=0.这是一个特殊形式的二阶非线性方程,称为Monge-Ampère方程(简写为 M-A 方程),有椭圆、双曲和抛物型之分.已有不少人研究过椭圆和双曲型的情况,这篇文章试图对抛物型 M-A 方程作-些研究.一般的二阶非线性方程     

Singular Solutions to Monge-Ampère Equation

We construct merely Lipschitz and $C^{1,α}$ with rational $α ∈ (0, 1 − 2/n]$ viscosity solutions to the Monge-Ampère equation with constant right hand side.     

一类Monge-Ampère方程的特征值问题

对一类Monge-Amp(e)re方程的特征值问题进行了研究.通过移动平面法证明了在凸对称区域内,Dirichlet问题的C2凹(凸)解一定是对称的.进而通过对常微分方程和椭圆形偏微分方程的讨论,得到一类n维单位球上特征值问题的非平凡解的存在性和正则性结果.     

一类Monge-Ampère方程的特征值问题

对一类Monge-Ampère方程的特征值问题进行了研究．通过移动平面法证明了在凸对称区域内,Dirichlet问题的C~2凹(凸)解一定是对称的．进而通过对常微分方程和椭圆形偏微分方程的讨论,得到一类n维单位球上特征值问题的非平凡解的存在性和正则性结果．     

Monge-Ampère方程的斜微商问题

本文讨论Monge-Ampere方程的斜微商问题,证明了二维Monge-Ampere方程经典解的存在性以及多维Monge-Ampere方程的广义解的存在性。     

Monge-Ampère Equation with Bounded Periodic Data

We consider the Monge-Ampère equation det $(D^2u) = f$ in $\mathbb{R}^n,$ where $f$ is a positive bounded periodic function. We prove that $u$ must be the sum of a quadratic polynomial and a periodic function. For $f ≡ 1,$ this is the classic result by Jörgens, Calabi and Pogorelov. For $f ∈ C^α,$ this was proved by Caffarelli and the first named author.     

A singular Monge-Ampère equation on unbounded domains

In this paper, we study the Dirichlet problem for a singular Monge-Amp`ere type equation on unbounded domains. For a few special kinds of unbounded convex domains, we find the explicit formulas of the solutions to the problem. For general unbounded convex domain ?, we prove the existence for solutions to the problem in the space C∞(?) ∩ C(?). We also obtain the local C1/2-estimate up to the ?? and the estimate for the lower bound of the solutions.     

Scalar differential invariants of symplectic Monge-Ampère equations

All second order scalar differential invariants of symplectic hyperbolic and elliptic Monge-Ampère equations with respect to symplectomorphisms are explicitly computed. In particular, it is shown that the number of independent second order invariants is equal to 7, in sharp contrast with general Monge-Ampère equations for which this number is equal to 2. We also introduce a series of invariant differential forms and vector fields which allow us to construct numerous scalar differential invariants of higher order. The introduced invariants give a solution of the symplectic equivalence of Monge-Ampère equations. As an example we study equations of the form u _xy + f(x, y, u _x , u _y ) = 0 and in particular find a simple linearization criterion.     

Bifurcation for Monge-Ampère equations on flat tori

In [4] (Theorem 2), we solved a Monge-Ampère equation, on a compact Riemannian manifold, which isnot a priori locally invertible. In particular, one cannot expect the solution to be unique. We investigate here, the way bifurcation phenomena may occur in such a case, with some explicit computations on flat tori.     

Integrable structures for a generalized Monge-Ampère equation

We consider a third-order generalized Monge-Ampère equation u_yyy ? u _xxy ² + u_xxxu_xyy = 0, which is closely related to the associativity equation in two-dimensional topological field theory. We describe all integrable structures related to it: Hamiltonian, symplectic, and also recursion operators. We construct infinite hierarchies of symmetries and conservation laws.     

A variational approach to complex Monge-Ampère equations

We show that degenerate complex Monge-Ampère equations in a big cohomology class of a compact Kähler manifold can be solved using a variational method, without relying on Yau’s theorem. Our formulation yields in particular a natural pluricomplex analogue of the classical logarithmic energy of a measure. We also investigate Kähler-Einstein equations on Fano manifolds. Using continuous geodesics in the closure of the space of Kähler metrics and Berndtsson’s positivity of direct images, we extend Ding-Tian’s variational characterization and Bando-Mabuchi’s uniqueness result to singular Kähler-Einstein metrics. Finally, using our variational characterization we prove the existence, uniqueness and convergence as k→∞ of k-balanced metrics in the sense of Donaldson both in the (anti)canonical case and with respect to a measure of finite pluricomplex energy.     

Problèmes de Monge-Ampère, courbes holomorphes et laminations

Riemann's Uniformization theorem is a classical tool for the study of elliptic problems on surfaces. Usually, the use of this theorem reflects the fact that the situation can be translated in a pseudo-holomorphic language: the solutions of the problem appearing as holomorphic curves for a suitable almost complex structure in a jet space. Often, the lack of compactness of the space of solutions of bounded energy is remarkably described by Gromov's compactness theorem on holomorphic curves. On the other hand for other problems, usually related to Monge-Ampère equations, a different type of lack of compactness appears; solutions with bounded energy converge and, furthermore, it is possible to describe what happens when the energy goes to infinity: the solutions tend to degenerate along holomorphic curves described by solutions of ODE. The goal of this article is to describe the "Monge-Ampère geometry" of the jet-space that corresponds to this phenonemon. We prove compactness results for the solutions of these problems, and show examples and applications of our technique. Furthermore, a moduli space of pointed solutions is exhibited with its structure of a riemaniann lamination. Submitted: December 1995, revised version: September 1996, final version: March 1997     

抛物型Monge-Ampère方程的第一边值问题

本文给出了方程(A)的解的存在性,唯一性和正则性结果。其中D为R~n中严格凸的,具有D~4光滑边界αD的有界区域,T>0,0<β<1为常数,f(x,t,u,p),F(x,t)为函数,满足:     

全平面上的齐次Monge-Ampère方程

本文证明了R2 上的齐次Monge Amp埁ｒｅ方程凸的古典解一定表示凸柱面 .     

关于复Monge-Ampère方程的一些研究

过去50年间,复Monge-Ampère方程是一个被广泛研究的主题,它在复分析、复几何和K?hler几何中有很多重要的应用.本文首先回顾一些经典结果,然后着重介绍关于复Monge-Ampère方程的Liouville定理、C~(1,α)估计和C~(2,α)估计,以及其在Sasakian几何中的一些应用.这些结果是与S.Dinew、管鹏飞、李超、李嘉禹和张享文等合作得到的.     

The Boundedness of Monge-Ampère Singular Integral Operators

We first define molecules for Hardy spaces H¹_F(\mathbbRⁿ)H^{1}_{\mathcal{F}}(\mathbb{R}^{n}) associated with a family F\mathcal{F} of sections which is closely related to the Monge-Ampère equation and prove their molecular characters. As an application, we show that Monge-Ampère singular operators are bounded on H¹_F(\mathbbRⁿ)H^{1}_{\mathcal{F}}(\mathbb{R}^{n}).