Combinatorial game theory (CGT) is a mathematical theory that can solve "sums of games", including difficult Go endgame problems. CGT deals with exact counting and determining the values of moves, which can be much more complicated than one might think. This theory has a branch called thermography, which is useful for playing endgames well with only a moderate amount of analysis. It also clarifies the meaning of sente and gote.
Our research interest is in efficient algorithms for combinatorial games. Some highlights: solving 5x5 Amazons and 6x5 Amazons; developing Decomposition Search and solving Go endgame puzzles as in the Berlekamp/Wolfe book; the first implementation of generalized thermography; developing Temperature Discovery Search (TDS) and TDS+, the first general forward search algorithms to compute or approximate the temperature of complex subgames.