Abstract
We prove quasi-monotonicity formulas for classical obstacle-type problems with energies being the sum of a quadratic form with Lipschitz coefficients, and a Hölder continuous linear term. With the help of those formulas we are able to carry out the full analysis of the regularity of free-boundary points following the approaches by Caffarelli (J Fourier Anal Appl 4(4–5), 383–402, 1998), Monneau (J Geom Anal 13(2), 359–389, 2003), and Weiss (Invent Math 138(1), 23–50, 1999).
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The first two authors have been supported by the Gruppo Nazionale per l’Analisi Matematica, la Probabilità e le loro Applicazioni (GNAMPA) of the Istituto Nazionale di Alta Matematica (INdAM).
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Communicated by L. Ambrosio.
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Focardi, M., Gelli, M.S. & Spadaro, E. Monotonicity formulas for obstacle problems with Lipschitz coefficients. Calc. Var. 54, 1547–1573 (2015). https://doi.org/10.1007/s00526-015-0835-0
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DOI: https://doi.org/10.1007/s00526-015-0835-0