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On the Measure and the Structure of the Free Boundary of the Lower Dimensional Obstacle Problem

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A Correction to this article was published on 04 July 2018

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Abstract

We provide a thorough description of the free boundary for the lower dimensional obstacle problem in \({\mathbb{R}^{n+1}}\) up to sets of null \({\mathcal{H}^{n-1}}\) measure. In particular, we prove

  1. (i)

    local finiteness of the (n−1)-dimensional Hausdorff measure of the free boundary,

  2. (ii)

    \({\mathcal{H}^{n-1}}\)-rectifiability of the free boundary,

  3. (iii)

    classification of the frequencies up to a set of Hausdorff dimension at most (n−2) and classification of the blow-ups at \({\mathcal{H}^{n-1}}\) almost every free boundary point.

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Change history

  • 04 July 2018

    One of the propositions of the paper on the classification of homogeneous solutions was found to be incorrect.

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Correspondence to Matteo Focardi.

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Communicated by A. Figalli

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Focardi, M., Spadaro, E. On the Measure and the Structure of the Free Boundary of the Lower Dimensional Obstacle Problem. Arch Rational Mech Anal 230, 125–184 (2018). https://doi.org/10.1007/s00205-018-1242-4

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  • DOI: https://doi.org/10.1007/s00205-018-1242-4

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