A computer program product is described for solving the traveling salesman problem in polynomial time. The probability distribution of the space of all paths is modeled in a configurational density distribution. A Hamiltonian is constructed specifying the costs, distance, or penalty associated with different legs of paths encompassed in the configurational density distribution. Starting at a maximum temperature where free energy dominates and the penalty function plays little role, the system is iteratively adapted to reduce the temperature in steps incrementally chosen to preserve the linear characteristic of the approximation, until a lower temperature state of reduced energy is reached in which a preferred set of paths can be identified from the configurational density distribution.