Comparing Levels of Bisimulation Quantifiers Logic with the mu-calculus
Giovanna D'Agostino, Giacomo Lenzi

Abstract:
In this paper we deal with the logic of Bisimulation Quantifiers
BQL. This is a logic extending PDL by means of bisimulation
quantifiers: an existential bisimulation quantifier acts like a
standard existential set quantifier but allows to look for a set not
only within the model, but in any other model which is bisimilar to
the given one. It is known that BQL has the same expressive power than
the mu-calculus. In this paper we give a finer look to this
correspondence, by defining a hierarchy for BQL and comparing it with
the mu-calculus hierarchy.