Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Model-theoretic characterization of intuitionistic propositional
  formulas   Notions of k-asimulation and asimulation are introduced as asymmetric
counterparts to k-bisimulation and bisimulation, respectively. It is proved
that a first-order formula is equivalent to a standard translation of an
intuitionistic propositional formula iff it is invariant with respect to
k-asimulations for some k, and then that a first-order formula is equivalent to
a standard translation of an intuitionistic propositional formula iff it is
invariant with respect to asimulations. Finally, it is proved that a
first-order formula is intuitionistically equivalent to a standard translation
of an intuitionistic propositional formula iff it is invariant with respect to
asimulations between intuitionistic models.

8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ