In mathematics and applications, quantum annealing is a method for finding solutions to combinatorial optimization problems and ground states of glassy systems using quantum fluctuations.Unlike simulated annealing, which employs the strategy of slow cooling (physically, or in simulation) to find the ground state of glassy systems (physical glass with a rugged potential energy landscape or a mathematical objective function with many local minima), Quantum annealing is basically annealing of glassy systems down to their global minimum (at least to a good approximation) using quantum fluctuations instead of thermal ones.
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