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COALA: Coalgebraic Logics and Applications

Coalgebraic semantics offers a generic framework to study a class of (typically non-normal) modal logic in a uniform way including, besides extensions of the logic K,

and many others. Results for particular logics are then obtained by simple instantiations of the coalgebraic framework.

The tutorial presents an overview of the state-of-the-art in coalgebraic logics, grouped around for main themes:

Modelling with Coalgebraic Logics
An introduction to coalgebras from the perspective of modal logic. Examples of coalgebraic models: Kripke models, (monotone) neighbourhood frames, game frames, probabilistic and labelled transition systems, weighted multigraphs, selection function models. Syntax and Semantics of coalgebraic logics, bisimulation and the Hennessy-Milner property.
Reasoning in Coalgebraic Logics
Axiom systems for coalgebraic logics, completeness and the finite model property in the general coalgebraic framework and applied to the examples above.
Complexity of Coalgebraic Logics
Generic sequent / tableaux systems for coalgebraic logics leading to uniform complexity bounds for the satisfiability problem of coalgebraic logics and a prototypical implementation, examples as above.
Combining Coalgebraic Logics
Construction principles for coalgebraic semantics, modular aspects of the Hennessy-Milner property, modular completeness and modular algorithms. Examples: Segala Systems and alternating systems (different combinations of probabilities and non-determinism), games with quantitative uncertainty (game frames with probabilistic information), logics of probabilistic knowledge.


Why Coalgebraic Logics?

Coalgebraic logics exhibit three major traits that make them a useful tool for modal reasoning:

Genericity
The tools and techniques developed in a coalgebraic framework are simultaneously applicable to a large class of logics
Compositionality
Coalgebraic techniques lend themselves to modular construction of systems with the same level of modularity at the logical level
Algorithms
Both genericity and compositionality manifest themselves also in the to the modular construction of decision procedures.
We hope that attendees will be able to identify and subsequently exploit coalgebraic aspects in their own research in the context of modelling, reasoning and mechanising modal logics, and profit from the large number of off-the-shelf results established in the coalgebraic framework.


Prerequisites

The tutorial provides an introduction to, and an overview of coalgebraic techniques in modal logics equally suitable for beginning PhD students and more experienced researchers. In particular, no prerequisite knowledge on coalgebras will be assumed.


Literature

A reader covering the four main themes of the tutorial will be provided.

General Theory of Coalgebras
Coalgebras and Modal Logic


Dirk Pattinson Monday, 28-Jan-2008 12:30:00 GMT [check HTML] [check CSS]