2011/09/23 by Fazly, Mostafa · 1 citation
#Analysis of PDEs (math.AP) #FOS: Mathematics
paper · doi:10.48550/arxiv.1109.5138
We establish Liouville type theorems for elliptic systems with various classes of non-linearities on ℝN. We show among other things, that a system has no semi-stable solution in any dimension, whenever the infimum of the derivatives of the corresponding non-linearities is positive. We give some immediate applications to various standard systems, such as the Gelfand, and certain Hamiltonian systems. The case where the infimum is zero is more interesting and quite challenging. We show that any C2(ℝN) positive entire semi-stable solution of the following Lane-Emden system, eqnarray* \hbox(Nλ,γ)50pt \arraylcl \hfill -Δu&=&λf(x) vp, \hfill -Δv&=&γf(x) uq, array.eqnarray* is necessarily constant, whenever the dimension N< 8+3α+(8+4α)/(q-1), provided p=1, q≥2 and f(x)= (1+|x|2)^\fracα2 . The same also holds for p=q≥2 provided N < 2+ (2(2+α))/(p-1) (p+√(p(p-1))). We also consider the case of bounded domains Ω⊂ℝN, where we extend results of Brown et al. \citebs and Tertikas \citete about stable solutions of equations to systems. At the end, we prove a Pohozaev type theorem for certain weighted elliptic systems.