Debraj Chakraborty worked on Distributed Games, and more specifically on Asynchronous Distributed Games with Causal Memory. The players of a team are distributed on several locations and have to take local decisions in order to attain a common goal, whatever the reaction of their adversarial environment. Each agent has only a partial view of the state of the whole system, and exchanges information by playing shared actions.
The decidability of the existence of a winning strategy in this class of games is a challenging open problem. The question is opened even in the case where the game has only five players. Debraj developed ad-hoc optimal algorithms for the four-player and a special case of five-player games. These results have been written up in the form of a report.