Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Reifenberg Flatness of Free Boundaries in Obstacle Problems with VMO
  Ingredients   We study the obstacle problem with an elliptic operator in divergence form.
We develop all of the basic theory of existence, uniqueness, optimal
regularity, and nondegeneracy of the solutions. These results, in turn, allow
us to begin the study of the regularity of the free boundary in the case where
the coefficients are in VMO.

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The categories of this paper are: adap-org
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: cs
4
The categories of this paper are: cond-mat
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
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The categories of this paper are: ao-sci