TY - JOUR AU - Aceto, Luca AU - Fokkink, Willem Jan AU - Glabbeek, Rob J. van AU - Ingólfsdóttir, Anna PY - 2003/08/07 Y2 - 2024/03/29 TI - Nested Semantics over Finite Trees are Equationally Hard JF - BRICS Report Series JA - BRICS VL - 10 IS - 27 SE - Articles DO - 10.7146/brics.v10i27.21795 UR - https://tidsskrift.dk/brics/article/view/21795 SP - AB - This paper studies nested simulation and nested trace semantics over the language BCCSP, a basic formalism to express finite process behaviour. It is shown that none of these semantics affords finite (in)equational axiomatizations over BCCSP. In particular, for each of the nested semantics studied in this paper, the collection of sound, closed (in)equations over a singleton action set is not finitely based. ER -