Dynamic epistemic semirings

This paper proposes a semiring formulation for reasoning about an agent's changing beliefs: a dynamic epistemic semiring (DES). A DES is a modal semiring extended with a revision operator. The revision operator is given a relational interpretation and a basic calculus is developed -- based on the revision operator a contraction operator is also defined. A DES only models actions on an agent's beliefs, whereas the real dynamic epistemic semirings also introduced in this paper facilitate actions on the world as well. To allow for iterated action both structures are extended with the Kleene star