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“Sometimes” and “not never” revisited

Journal of the ACMPublished 2 January 1986Open access
E. Allen Emerson, Joseph Y. Halpern
Citations996
SJR quartileQ1
SJR score2.25
SNIP3.16
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TL;DR

A language, CTL*, in which a universal or existential path quantifier can prefix an arbitrary linear time assertion, is defined and the expressive power of a number of sublanguages is compared.

Abstract

The differences between and appropriateness of branching versus linear time temporal logic for reasoning about concurrent programs are studied. These issues have been previously considered by Lamport. To facilitate a careful examination of these issues, a language, CTL * , in which a universal or existential path quantifier can prefix an arbitrary linear time assertion, is defined. The expressive power of a number of sublanguages is then compared. CTL* is also related to the logics MPL of Abrahamson and PL of Harel, Kozen, and Parikh. The paper concludes with a comparison of the utility of branching and linear time temporal logics.

Keywords

Computer Science