Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: FO Model Checking on Posets of Bounded Width   Over the past two decades the main focus of research into first-order (FO)
model checking algorithms have been sparse relational structures-culminating in
the FPT-algorithm by Grohe, Kreutzer and Siebertz for FO model checking of
nowhere dense classes of graphs [STOC'14], with dense structures starting to
attract attention only recently. Bova, Ganian and Szeider [LICS'14] initiated
the study of the complexity of FO model checking on partially ordered sets
(posets). Bova, Ganian and Szeider showed that model checking existential FO
logic is fixed-parameter tractable (FPT) on posets of bounded width, where the
width of a poset is the size of the largest antichain in the poset. The
existence of an FPT algorithm for general FO model checking on posets of
bounded width, however, remained open. We resolve this question in the positive
by giving an algorithm that takes as its input an $n$-element poset $\cal P$ of
width $w$ and an FO logic formula $\phi$, and determines whether $\phi$ holds
on $\cal P$ in time $f(\phi,w)\cdot n^2$.

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The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
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The categories of this paper are: chao-dyn
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The categories of this paper are: eess
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The categories of this paper are: econ
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
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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: nucl-th