Maximum principles for a class of semilinear elliptic boundary-value problems
Hailiang Zhang · Bulletin of the Australian Mathematical Society · 1995
For years it has remained a problem to find suitable functionals satisfying certain maximum principles for solutions of the equation Δu + f(x, u) = 0. In this paper, maximum principles for certain functionals which are defined on solutions of semilinear elliptic equations subject to mixed or Robin boundary conditions are obtained. The principles derived may be used to deduce bounds on important quantities in physical problems of interest.