CCS with Hennessy's merge has no finite-equational axiomatization

L. Aceto, W.J. Fokkink, A. Ingólfsdóttir, B. Luttik

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This paper confirms a conjecture of Bergstra and Klop's from 1984 by establishing that the process algebra obtained by adding an auxiliary operator proposed by Hennessy in 1981 to the recursion free fragment of Milner's Calculus of Communicating Systems is not finitely based modulo bisimulation equivalence. Thus, Hennessy's merge cannot replace the left merge and communication merge operators proposed by Bergstra and Klop, at least if a finite axiomatization of parallel composition modulo bisimulation equivalence is desired. © 2004 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)377-405
JournalTheoretical Computer Science
Issue number3
Publication statusPublished - 2005

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