This paper is motivated by the observation that solutions to certain variational inequalities involving partial differential operators of the form div A ( x , u , ∇ u ) + B ( x , u , ∇ u ) \operatorname {div} A(x,u,\nabla u) + B(x,u,\nabla u) , where A A and B B are Borel measurable, are solutions to the equation div A ( x , u , ∇ u ) + B ( x , u , ∇ u ) = μ \operatorname {div} A(x,u,\nabla u) + B(x,u,\nabla u) = \mu for some nonnegative Radon measure μ \mu . Among other things, it is shown that if u u is a Hölder continuous solution to this equation, then the measure μ \mu satisfies the growth property μ [ B ( x , r ) ] ⩽ M r n − p + ε \mu [B(x,r)] \leqslant M{r^{n - p + \varepsilon }} for all balls B ( x , r ) B(x,r) in R n {{\mathbf {R}}^n} . Here ε \varepsilon depends on the Hölder exponent of u u while p > 1 p > 1 is given by the structure of the differential operator. Conversely, if μ \mu is assumed to satisfy this growth condition, then it is shown that u u satisfies a Harnack-type inequality, thus proving that u u is locally bounded. Under the additional assumption that A A is strongly monotonic, it is shown that u u is Hölder continuous.
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