Harnack's Inequality for Cooperative Weakly Coupled Elliptic Systems
Ghosh, Mrinal K.
Marcus, Steven I.
MetadataShow full item record
We consider cooperative, uniformly elliptic systems, with bounded coefficients and coupling in the zeroth-order terms. We establish two analogues of Harnack's inequality for this class of systems. A weak version is obtained under fairly general conditions, while imposing an irreducibility condition on the coupling coefficients we obtain a stronger version of the inequality. This irreducibility condition is also necessary for the existience of a Harnack constant for this class of systems. A Harnack inequality is also obtained for a class of superharmonic functions.