Nonexistence of Positive Solutions to Semilinear Elliptic Inequalities for Polyharmonic Operator

In this paper, we study the nonexistence of positive solution for some higher-order semilinear elliptic inequality particularly involving polyharmonic operator: Δku(x) ≥ x1 α1 x2 α2… xn αnuq(x), where k ∈ ℕ,q > 1, x = (x1,x2,…,xn) and αi ∈ ℝ,i = 1,2,…,n. The purpose of this paper is to establish conditions on values of αi,i = 1,2,…,n for the nonexistence of positive solution to this problem in a bounded and unbounded domain. The main tools are a priori estimates and integral inequalities. Using the test function method, we derive first a priori estimates for solutions of the inequality based on integral inequalities and on the weak formulation of the problem with an optimal choice of test functions and then we formulate the nonexistence condition of the solution of the problem. The choice of such functions is determined by the nonlinear characters of the problem and depends on the concept of solutions that we are dealing with.

semilinear elliptic inequalities, anisotropic singularities, polyharmonic operators, apriori estimates and nonexistence of solutions