Equational Coalgebraic Logic

  • Authors:
  • Alexander Kurz;Raul Leal

  • Affiliations:
  • Computer Science Departament, University of Leicester, Leicester, UK;ILLC, Universiteit van Amsterdam, Amsterdam, The Netherlands

  • Venue:
  • Electronic Notes in Theoretical Computer Science (ENTCS)
  • Year:
  • 2009

Quantified Score

Hi-index 0.00

Visualization

Abstract

Coalgebra develops a general theory of transition systems, parametric in a functor T; the functor T specifies the possible one-step behaviours of the system. A fundamental question in this area is how to obtain, for an arbitrary functor T, a logic for T-coalgebras. We compare two existing proposals, Moss's coalgebraic logic and the logic of all predicate liftings, by providing one-step translations between them, extending the results in [Raul Andres Leal, Predicate liftings versus nabla modalities, Electr. Notes Theor. Comput. Sci. 203 (2008), no. 5, 195-220] by making systematic use of Stone duality. Our main contribution then is a novel coalgebraic logic, which can be seen as an equational axiomatization of Moss's logic. The three logics are equivalent for a natural but restricted class of functors. We give examples showing that the logics fall apart in general. Finally, we argue that the quest for a generic logic for T-coalgebras is still open in the general case.