Existence and large radial solutions for an elliptic system under finite new Keller-Osserman integral conditions
Dragos-Patru Covei
TL;DR
This work extends Keller–Osserman theory to a coupled semilinear elliptic system with radial weights by developing KO-type transforms and subharmonic barriers under finite reciprocal integral conditions. It proves the existence of infinitely many entire positive radial solutions for a nonempty set of central values, and shows this set is closed; boundary central values yield large solutions that blow up at infinity. The paper also analyzes the compatibility and distinctions between the ELRS framework and Covei2017 results, providing a common example and clarifying when each regime applies. Overall, it advances understanding of existence and asymptotic behavior for weighted, nonlinear elliptic systems with general nonlinearities.
Abstract
We study the semilinear elliptic system \[ Δu = p(|x|)\,g(v), \qquad Δv = q(|x|)\,f(u), \qquad x \in \mathbb{R}^n,\; n \geq 3, \] under new Keller--Osserman-type integral conditions on the nonlinearities $f,g$ and decay constraints on the radial weights $p,q$. Within this framework we prove: (i) existence of infinitely many entire positive radial solutions for admissible central values; (ii) closedness of the set of all admissible central values; and (iii) largeness (blow-up at infinity) of solutions at boundary points. The analysis combines comparison principles, compactness arguments, and Keller--Osserman transforms, thereby extending classical theory to coupled elliptic systems with general nonlinearities and weights.
