An Undecidability Proof for the Plan Existence Problem
Researchers have proven that the plan existence problem in modal logic is undecidable. This problem involves determining if a sequence of epistemic actions can achieve a specified goal, given an initial state and a set of actions. The proof holds even when action preconditions have a modal depth of one and there are no postconditions, resolving a previously unknown question about the problem's decidability. AI
IMPACT Establishes theoretical limits for AI planning agents operating in epistemic domains.