Topological semantics for computation tree logics

抄録

Descriptive set theory is used to compare the expressive power of sublogics of CTL*. One application is a simple proof of the fact that no equivalent CTL formula exist for the CTL* formula EGF(p).The proof consists of showing that in a suitable semantics CTL formulas correspond to Borel sets while [[EGF(p)]] is analytic but not Borel.