Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A characterization of injective subsets in R^n with maximum norm   We characterize all (absolute) 1-Lipschitz retracts Q of R^n with the maximum
norm. Omitting two technical details, they coincide with the subsets written as
the solution set of (at most) 2n inequalities like follows. For every
coordinate i=1,...,n, there is a lower and an upper bound L,U : R^{n-1} -> R of
1-Lipschitz maps with L \leq U and the inequalities read
  L(x_1,...,x_{i-1},x_{i+1},...,x_n) \leq x_i \leq
U(x_1,...,x_{i-1},x_{i+1},...,x_n)
  These sets are also exactly the injective subsets; meaning those Q such that
every 1-Lipschitz map A -> Q, defined on a subset A of a metric space B,
possesses a 1-Lipschitz extension B -> Q.

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The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
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The categories of this paper are: gr-qc
1
The categories of this paper are: cs
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The categories of this paper are: stat
8
The categories of this paper are: hep-ex
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-th
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The categories of this paper are: math-ph