An Algebraic Approach to Dynamic Epistemic Logic

Dynamic epistemic logic plays a key role in reasoning about multi-agent systems. Past approaches to dynamic epistemic logic have typically been focused on actions whose primary purpose is to communi- cate information from one agent to another. These actions are unable to alter the valuation of any proposition within the system. In fields such as security, it is easy to imagine situations in which this sort of action would be insufficient. We expand the algebraic framework presented by M. Sadrzadeh (14) to include both communication actions and dynamic actions that change the state of the system. Furthermore, we propose a new modality that captures both epistemic and propositional changes resulting from the agents' actions.