Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Flat Wall Theorem for Matching Minors in Bipartite Graphs   A major step in the graph minors theory of Robertson and Seymour is the
transition from the Grid Theorem which, in some sense uniquely, describes areas
of large treewidth within a graph, to a notion of local flatness of these areas
in form of the existence of a large flat wall within any huge grid of an
H-minor free graph. In this paper, we prove a matching theoretic analogue of
the Flat Wall Theorem for bipartite graphs excluding a fixed matching minor.
Our result builds on a a tight relationship between structural digraph theory
and matching theory and allows us to deduce a Flat Wall Theorem for digraphs
which substantially differs from a previously established directed variant of
this theorem.

18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: comp-gas
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The categories of this paper are: patt-sol
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The categories of this paper are: acc-phys