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\iteman{io-port 01136647}
\itemau{Kasangian, Stefano; Vigna, Sebastiano}
\itemti{The topos of labelled trees: A categorical semantics for SCCS.}
\itemso{Ann. Soc. Math. Pol., Ser. IV, Fundam. Inf. 32, No.1, 27-45 (1997).}
\itemab
Summary: We give a semantics for SCCS using the constructions of the topos of labelled trees. The semantics accounts for all aspects of the original formulation of SCCS, including unbounded non-determinism. Then, a partial solution to the problem of characterizing bisimulation in terms of a class of morphisms is proposed. We define a class of morphisms of the topos of trees, called conflict preserving, such that two trees $T$ and $U$ are bisimilar iff there is a pair of conflict preserving morphisms $f: T\to U$ and $g:U\to T$ such that $fgf= f$ and $gfg= g$. It is the first characterization which does not require the existence of a third quotient object. The results can be easily extended to more general transition systems.
\itemrv{~}
\itemcc{}
\itemut{semantics for SCCS}
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