Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: It Is Easy to Be Wise After the Event: Communicating Finite-State
  Machines Capture First-Order Logic with "Happened Before"   Message sequence charts (MSCs) naturally arise as executions of communicating
finite-state machines (CFMs), in which finite-state processes exchange messages
through unbounded FIFO channels. We study the first-order logic of MSCs,
featuring Lamport's happened-before relation. We introduce a star-free version
of propositional dynamic logic (PDL) with loop and converse. Our main results
state that (i) every first-order sentence can be transformed into an equivalent
star-free PDL sentence (and conversely), and (ii) every star-free PDL sentence
can be translated into an equivalent CFM. This answers an open question and
settles the exact relation between CFMs and fragments of monadic second-order
logic. As a byproduct, we show that first-order logic over MSCs has the
three-variable property.

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The categories of this paper are: funct-an
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The categories of this paper are: astro-ph
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: stat
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The categories of this paper are: q-fin
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th
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The categories of this paper are: math-ph
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
3
The categories of this paper are: physics
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The categories of this paper are: alg-geom