Conceitos Básicos
Transition algebras enhance many-sorted first-order logic with features from dynamic logics, enabling the formal specification and verification of concurrent systems.
Resumo
The paper introduces a logical system of transition algebras (TA) that extends many-sorted first-order logic with constructs for modeling the behavior of concurrent systems. The key aspects are:
- Signatures: TA signatures consist of many-sorted algebraic signatures extended with transition labels and monotonic function symbols.
- Models: TA models are many-sorted algebras equipped with binary relations that interpret the transition labels.
- Sentences: TA sentences include compositions, unions, and transitive closures of transition relations, similar to the actions used in dynamic logics. This increases the expressivity compared to many-sorted first-order logic.
- Entailment: The authors define a basic entailment relation for reasoning about atomic sentences and a dynamic entailment relation that handles actions, Boolean connectives, and quantifiers. They show that the dynamic entailment relation is ω1-compact, but the satisfaction relation is not.
- Completeness: Due to the lack of compactness, the authors develop a forcing technique to prove completeness for the restriction of TA to countable signatures.
- Application: The authors demonstrate the expressivity of TA by encoding the syntax and operational semantics of Milner's Calculus of Communicating Systems (CCS).
The proposed TA logic aims to provide a denotational semantics for algebraic specification languages that are executable by term rewriting, combining the modular properties of the logic underlying CafeOBJ with the rich expressivity of rewriting logic.