Epistemic Logic with Functional Dependency Operator
  Epistemic logic with non-standard knowledge operators, especially the
"knowing-value" operator, has recently gathered much attention. With the
"knowing-value" operator, we can express knowledge of individual variables, but
not of the relations between them in general. In this paper, we propose a new
operator Kf to express knowledge of the functional dependencies between
variables. The semantics of this Kf operator uses a function domain which
imposes a constraint on what counts as a functional dependency relation. By
adjusting this function domain, different interesting logics arise, and in this
paper we axiomatize three such logics in a single agent setting. Then we show
how these three logics can be unified by allowing the function domain to vary
relative to different agents and possible worlds. A multiagent axiomatization
is given in this case.
