Existence of Positive Harmonic Functions

Interpolation by Positive Harmonic Functions

A natural interpolation problem in the cone of positive harmonic functions is considered and the corresponding interpolating sequences are geometrically described.

Some Properties of Positive Harmonic Functions

From a monotonicity property, we derive several results characterizing positive harmonic functions in the unit ball in R and positive measures on the unit sphere Sn−1. Let Bn = {x ∈ Rn : |x| < 1}, n ≥ 2 be the unit ball in Rn and Sn−1 = ∂Bn be the unit sphere. From a monotonicity property, we derive several results characterizing positive harmonic functions in Bn and positive measures on Sn−1. ...

Harmonic Functions with Positive Real Part

In this paper, the class of harmonic functions f = h+ ḡ with positive real part and normalized by f(ζ) = 1, (|ζ| < 1) is studied, where h and g are analytic in U = {z : |z| < 1}. Some properties of this class are searched. Sharp coefficient relations are given for functions in this class. On the other hand, the author make use of Alexander integral transforms of certain analytic functions (whic...

A lower estimate of harmonic functions

We shall give a lower estimate of harmonic‎ ‎functions of order greater than one in a half space‎, ‎which‎ ‎generalize the result obtained by B‎. ‎Ya‎. ‎Levin in a half plane‎.

Monotonicity of Harnack Inequality for Positive Invariant Harmonic Functions