| In this paper,we first study the following autonomous Schr(?)dinger-Poisson system where f∈C(R,R),and there exists μ>3 such that 1/μf(t)t≥ F(t)>,0 F(t)=∫0t f(s)ds,t∈R.We obtain infinitely many high energy radial solutions for the system by using a method generating a Palais-Smale sequence with an extra property related to Poho(?)aev identity and the minimax principle.Secondly,we consider system(0.0.1)with f(u)=a(x)|u|p-2u+λk(x)u,namely where p ∈(2,3),μ>0 small enough and λ>0.k(x)is a positive function,a(x)∈ C(R3)and a is sign changing,this is why we call it indefinite nonlineari-ty.We establish the multiple solutions of system(0.0.2)by using the symmetric mountain-pass theorem and a version of Clark’s theorem. |
