Construction of solutions to a nonlinear critical elliptic system via local Pohozaev identities

TL;DR

This paper constructs multiple non-radial solutions for a coupled nonlinear elliptic system with critical Sobolev growth using local Pohozaev identities, extending previous results to more general conditions and higher dimensions.

Contribution

It introduces a novel method combining local Pohozaev identities with reduction techniques to find solutions under weaker symmetry assumptions.

Findings

Constructed an unbounded sequence of solutions with arbitrarily large energy.

Extended previous single-equation results to coupled systems in higher dimensions.

Overcame difficulties due to coupling exponent and weaker symmetry conditions.

Abstract

In this paper, we investigate the following elliptic system with Sobolev critical growth $-\Delta u+P(|y'|,y'')u=u^{2^*-1}+\frac{\beta}{2} u^{\frac{2^*}{2}-1}v^{\frac{2^*}{2}},\ y\in R^N$, $-\Delta v+Q(|y'|,y'')v=v^{2^*-1}+\frac{\beta}{2} v^{\frac{2^*}{2}-1}u^{\frac{2^*}{2}}$, $y\in R^N ,u,v>0,u,\,v\in H^1(R^N), $ where~$(y',y'')\in R^2 \times R^{N-2}$, $P(|y'|,y''), Q(|y'|,y'')$ are bounded non-negative function in $R^+\times R^{N-2}$, $2^*=\frac{2N}{N-2}$. By combining a finite reduction argument and local Pohozaev type of identities, assuming that $N\geq 5$ and $r^2(P(r,y'')+\kappa ^2Q(r,y''))$ have a common topologically nontrivial critical point, we construct an unbounded sequence of non-radial positive vector solutions of synchronized type, whose energy can be made arbitrarily large. Our result extends the result of a single critical problem by [Peng, Wang and Yan,J. Funct. Anal. 274: 2606-2633, 2018]. The novelties mainly include the following two aspects. On one hand, when $N\geq5$, the coupling exponent $\frac{2}{N-2}<1$, which creates a great trouble for us to apply the perturbation argument directly. This constitutes the main difficulty different between the coupling system and a single equation. On the other hand, the weaker symmetry conditions of $P(y)$ and $Q(y)$ make us not estimate directly the corresponding derivatives of the reduced functional in locating the concentration points of the solutions, we employ some local Pohozaev identities to locate them.