Epistemic Logic for Communication Chains

Jeffrey Kane and Pavel Naumov

The paper considers epistemic properties of linear communication chains. It describes a sound and complete logical system that, in addition to the standard axioms of S5 in a multi-modal language, contains two non-trivial axioms that capture the linear structure of communication chains. [pdf]

R.E. Axiomatization of Conditional Independence

Pavel Naumov and Brittany Nicholls

The paper investigates properties of the conditional independence relation between pieces of information. This relation is also known in the database theory as embedded multi-valued dependency. In 1980, Parker and Parsaye-Ghomi established that the properties of this relation can not be described by a finite system of inference rules. In 1995, Herrmann proved that the propositional theory of this relation is undecidable. The main result of this paper is a complete recursively enumerable axiomatization of this theory. [pdf]