Symmetry occurs in many problems in aritifical intelligence. For example, in the n-queens problem, the chessboard can be rotated 90°. As a second example, several machines in a factory might have the same capacity. In a production schedule, we might therefore be able to swap the jobs on machines with the same capacity. As a third example, two people within a company might have the same skills. Given a staff roster, we might therefore be able to interchange these two people. And as a fourth example, when configuring a computer, two memory boards might be identical. We might therefore be able to swap them around without changing the performance of the computer.


Symmetry Breaking Symmetric Solution Constraint Programming Production Schedule Global Constraint 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Toby Walsh
    • 1
  1. 1.National ICT Australia and School of CSEUniversity of New South WalesSydneyAustralia

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