Abstract:
The complexity classes defined on the basis of branching programs are considered. Some basic relations are established between the complexity classes defined by the probabilistic and quantum branching programs (measure-once, as well as measure-many), computing with bounded or unbounded error. To prove these relations, we developed a method of "linear simulation" of a quantum branching program and a method of "quantum simulation" of a probabilistic branching program. © Pleiades Publishing, Ltd. 2007.