encoded, even if the coding is arbitrary large. Turing machine is more powerful than quantum computer, in fact, quantum computer is in the class of BQP, which is a subset of PSPACE problem, which is a subset of Turing machine. Analog computer, in terms of computing power, cannot exceed Turing machine. People think analog computer is better because they confuse hypercomputing with analog. Hyper computing model is not even theoretical well defined.