| It is well known that the eigenvalues and eigenfunctions of linear differential op-erators are one of the core of operator theory and one of the foundations for studying corresponding non-linear problems.In this paper,the eigenvalue problem of weighted fractional Laplacian operators with Neumann boundary conditions (?) is studied,where λ>0,s ∈(0,1),m,c ∈ C0,1(Ω).When c(x)= 0,the necessary and sufficient condition for the existence of positive principal eigenvalues for the above problems is that the weight function satisfies the con-dition ∫Ωm(x)dx<0 and m(x0)>0 for some x0,and generalize the results of Montefusco et al.[Discrete Coitin.Dynam.Syst.B,2013]to s ∈(0,1).We also prove the blow-up property of eigenvalues,that is,for a sequence of weighted functions {mj}j=1∞ we prove the sufficient and necessary conditions for lim j>∞λ1(mj)=∞.This conclusion generalizes the classical Laplacian operator case[Umezu K.,et al.,Proc.R.Soc.Edinb.,2007]to the fractional Laplacian operator.When m(x)≡ 1,we prove the existence of principal eigenvalue λ1 and its correspond-ing principal eigenvalue function.We also prove λ1 is simple and any other solution of the above question with λ>λ1,changes sign.Next,we study the logistic equation:It is proved that the necessary and sufficient condition for the existence of a unique positive solution is λ>λ1 and the regularity of the positive solution.The results of Dirichlet boundary case[Alves M.O.,et aL.,Proc.R.Soc.Edinb.,2017]are extended to Neumann boundary case. |