Optical Techniques For Increasing The Efficiency Of Tree Search Algorithms

Artificial Intelligence problems are often formulated as search trees. These problems suffer from exponential growth of the solution space with problem size. Consequently, solutions based on exhaustive search are generally impractical. To overcome the combinatorial explosion, forward-checking techniques are employed to prune the search space down to a manageable size before or during the actual search procedure. Boolean matrices are a natural data representation for those problems in which the initial problem information is given in the form of a set of binary constraints. In this paper optical implementations of Boolean matrix operations are described for manipulating the constraint matrices to perform forward-checking and thereby increase the search efficiency. Architectural issues affecting the speed of these techniques are discussed.