Further Formalization of the Process Algebra CCS in HOL4

In this project, we have extended previous work on the formalization of the process algebra CCS in HOL4. We have added full supports on weak bisimulation equivalence and observation congruence (rooted weak equivalence), with related definitions, theorems and algebraic laws. Some deep lemmas were also formally proved in this project, including Deng Lemma, Hennessy Lemma and several versions of the "Coarsest congruence contained in weak equivalence". For the last theorem, we have proved the full version (without any assumption) based on ordinals.