Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Hurewicz covering property and slaloms in the Baire space   According to a result of Kocinac and Scheepers, the Hurewicz covering
property is equivalent to a somewhat simpler selection property: For each
sequence of large open covers of the space one can choose finitely many
elements from each cover to obtain a groupable cover of the space. We simplify
the characterization further by omitting the need to consider sequences of
covers: A set of reals $X$ satisfies the Hurewicz property if, and only if,
each large open cover of $X$ contains a groupable subcover. This solves in the
affirmative a problem of Scheepers.
  The proof uses a rigorously justified abuse of notation and a "structure"
counterpart of a combinatorial characterization, in terms of slaloms, of the
minimal cardinality b of an unbounded family of functions in the Baire space.
In particular, we obtain a new characterization of $\b$.

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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
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The categories of this paper are: patt-sol
18
The categories of this paper are: econ
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The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio