We study a second order elliptic partial differential equation for which a maximum principle is not available and whose nonlinearity is not C1C^1. We discuss the role of a pointwise gradient bound and we derive a monotonicity estimate near flat points of the free boundary.

Contact details are reproduced from the original publication and may be historical.

Marcelo Montenegro

Dep. de Matemática, Universidade Estadual de Campinas – IMECC, Rua Sérgio Buarque de Holanda 651, Campinas-SP CEP 13083-859, Brazil

msm@ime.unicamp.br

Enrico Valdinoci

Dip. di Matematica, Università di Milano, Via Saldini 50, 20133 Milano, Italy
and: Istituto di Matematica Applicata e Tecnologie Informatiche, Consiglio Nazionale delle Ricerche, Via Ferrata, 1, 27100 Pavia, Italy

enrico@math.utexas.edu
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M. Montenegro, E. Valdinoci. “Pointwise Estimates and Monotonicity Formulas without Maximum Principle.” Journal of Convex Analysis 20 (2013), No. 1, 199–220. https://doi.org/10.68381/jca20012