A proof of the fractional Lane--Emden conjecture

Let $n\ge2$, $00$. We prove a Liouville theorem for the fractional Lane--Emden system \[ (-Δ)^s u=v^p,\qquad (-Δ)^s v=u^q, \qquad u, v>0 \qquad\text{in }\R^n. \] More precisely, we show that the system does not have a strictly positive entire solution whenever \[ \frac1{p+1}+\f