  We propose a path-integral Monte Carlo quantum annealing scheme for the
symmetric Traveling Salesman Problem, based on a highly constrained Ising-like
representation, and we compare its performance against standard thermal
Simulated Annealing. The Monte Carlo moves implemented are standard, and
consist in restructuring a tour by exchanging two links (2-opt moves). The
quantum annealing scheme, even with a drastically simple form of kinetic
energy, appears definitely superior to the classical one, when tested on a 1002
city instance of the standard TSPLIB.
