Adams, David R.Nussenzveig Lopes, Helena J.2018-08-282018-08-281997-10-31Adams, D. R., & Nussenzveig Lopes, H. J. (1997). Nonlinear weakly elliptic 2 x 2 systems of variational inequalities with unilateral obstacle constraints. <i>Electronic Journal of Differential Equations, 1997</i>(18), pp. 1-20.1072-6691https://hdl.handle.net/10877/7636We study 2X2 systems of variational inequalities which are only weakly elliptic; in particular, these systems are not necessarily monotone. The prototype differential operator is the (vector-valued) p-Laplacian. We prove, under certain conditions, the existence of solutions to the unilateral obstacle problem. This work extends the results by the authors in [Annali di Mat. Pura ed Appl., 169(1995), 183--201] to nonlinear operators. In addition, we address the question of determining function spaces on which the p-Laplacian is a bounded nonlinear operator. This question arises naturally when studying existence for these systems.Text20 pages1 file (.pdf)enAttribution 4.0 Internationalp-LaplacianObstacle problemNon-monotone systems of variational inequalitiesArticle