The Point Algebra for Branching Time Revisited

Temporal reasoning with nonlinear models of time have been used in many areas of artificial intelligence. In this paper we focus on the model of branching time which has been proven successful for problems such as planning. We investigate the computational complexity of the point algebra for branching time extended with disjunctions and show that there are exactly five maximal tractable sets of relations. We also give an improved algorithm for deciding satisfiability of the point algebra with a time complexity comparable to that of path consistency checking algorithms.

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