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A stored programming computer model is that where a central memory is used to store both instructions and data that they operate on. Basically all the classical computers of today that follow the von Neumann architecture use the stored programming model. During program execution the CPU reads instructions or data from the RAM and places it in the various registers such as Instruction Register (IR) and other general purpose registers.

My question is whether such a stored programming model is applicable to a Quantum Computer or not, since because of the no-cloning theorem it is not possible to clone any arbitrary quantum state.

It means that if we have some qubits in some state stored in a memory register then because of the no-cloning theorem the Quantum Computer processor will not be able to read or copy those qubits from the memory to some internal registers.

Sanchayan Dutta
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K Sarkar
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1 Answers1

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Yes, you can encode a program into your qubits in exactly the same way you'd encode a program into bits and then run circuits that interpret the program. One might hope that you could encode the program in some fancy exponentially efficient way, but in Mike&Ike they prove that's not possible. Because there's no exponential advantage, and because the operations needed to read and decode the program are billions of time more expensive on a quantum computer, you want to store the program in the classical control computer in almost all cases.

Craig Gidney
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