A Phase Transition in Minesweeper
This work provides insights into computational hardness and algorithmic barriers in puzzle games, which is incremental for theoretical computer science.
The paper investigates the average-case complexity of Minesweeper, showing it exhibits a phase transition similar to SAT, where above a critical mine density, logical inference becomes nearly impossible, with hardness peaking at this transition.
We study the average-case complexity of the classic Minesweeper game in which players deduce the locations of mines on a two-dimensional lattice. Playing Minesweeper is known to be co-NP-complete. We show empirically that Minesweeper exhibits a phase transition analogous to the well-studied SAT phase transition. Above the critical mine density it becomes almost impossible to play Minesweeper by logical inference. We use a reduction to Boolean unsatisfiability to characterize the hardness of Minesweeper instances, and show that the hardness peaks at the phase transition. Furthermore, we demonstrate algorithmic barriers at the phase transition for polynomial-time approaches to Minesweeper inference. Finally, we comment on expectations for the asymptotic behavior of the phase transition.