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Estimates for k -Hessian operator and some applications

Dongrui Wan (2013)

Czechoslovak Mathematical Journal

The k -convex functions are the viscosity subsolutions to the fully nonlinear elliptic equations F k [ u ] = 0 , where F k [ u ] is the elementary symmetric function of order k , 1 k n , of the eigenvalues of the Hessian matrix D 2 u . For example, F 1 [ u ] is the Laplacian Δ u and F n [ u ] is the real Monge-Ampère operator det D 2 u , while 1 -convex functions and n -convex functions are subharmonic and convex in the classical sense, respectively. In this paper, we establish an approximation theorem for negative k -convex functions, and give several...

Estimates for the Poisson kernels and their derivatives on rank one NA groups

Ewa Damek, Andrzej Hulanicki, Jacek Zienkiewicz (1997)

Studia Mathematica

For rank one solvable Lie groups of the type NA estimates for the Poisson kernels and their derivatives are obtained. The results give estimates on the Poisson kernel and its derivatives in a natural parametrization of the Poisson boundary (minus one point) of a general homogeneous, simply connected manifold of negative curvature.

Estimation of Green's function on piecewise Dini-smooth bounded Jordan domains

Mohamed Amine Ben Boubaker, Mohamed Selmi (2013)

Colloquium Mathematicae

We establish inequalities for Green functions on general bounded piecewise Dini-smooth Jordan domains in ℝ². This enables us to prove a new version of the 3G Theorem which generalizes its previous version given in [M. Selmi, Potential Anal. 13 (2000)]. Using these results, we give a comparison theorem for the Green kernel of Δ and the Green kernel of Δ - μ, where μ is a nonnegative and exact Radon measure.

Exact solutions to some external mixed problems in potential theory

Valery I. Fabrikant (1986)

Aplikace matematiky

A new and elegant procedure is proposed for the solution of mixed potential problems in a half-space with a circular line of division of boundary conditions. The approach is based on a new type of integral operators with special properties. Two general external problems are solved; i) An arbitrary potential is specified at the boundary outside a circle, and its normal derivative is zero inside; ii) An arbitrary normal derivative is given outside the circle, and be potential is zero inside. Several...

Examples of non-local time dependent or parabolic Dirichlet spaces

Niels Jacob (1993)

Colloquium Mathematicae

In [23] M. Pierre introduced parabolic Dirichlet spaces. Such spaces are obtained by considering certain families ( E ( τ ) ) τ of Dirichlet forms. He developed a rather far-reaching and general potential theory for these spaces. In particular, he introduced associated capacities and investigated the notion of related quasi-continuous functions. However, the only examples given by M. Pierre in [23] (see also [22]) are Dirichlet forms arising from strongly parabolic differential operators of second order. To...

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