In this paper we introduce a notion of almost minimizers for certain variational problems governed by the fractional Laplacian, with the help of the Caffarelli-Silvestre extension. In particular, we study almost fractional harmonic functions and almost minimizers for the fractional obstacle problem with zero obstacle. We show that for a certain range of parameters, almost minimizers are almost Lipschitz or C1,β-regular.
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Regularity of almost-minimizers of Hölder-coefficient surface energies
We study almost-minimizers of anisotropic surface energies defined by a Hölder continuous matrix of coefficients acting on the unit normal direction to the surface. In this generalization of the Plateau problem, we prove almost-minimizers are locally Hölder continuously differentiable at regular points and give dimension estimates for the size of the singular set. We work in the framework of sets of locally finite perimeter and our proof follows an excess-decay type argument.
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- Award ID(s):
- 1853993
- PAR ID:
- 10571594
- Publisher / Repository:
- AIMS
- Date Published:
- Journal Name:
- Discrete and Continuous Dynamical Systems
- Volume:
- 42
- Issue:
- 7
- ISSN:
- 1078-0947
- Page Range / eLocation ID:
- 3233
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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