What is the difference between physical and logical qubit?

Question

What is the difference between physical and logical qubit?

Hope someone can help me in this matter, I can’t determine exactly what the difference is.

Best, Dirma

Answer 1

A logical qubit is one that you can use for programming that contains a superposition of states | 0> and | 1>. It can be implemented using a simulator running on a regular binary processor on your desktop or laptop so that you can develop and debug quantum algorithms. (The representation of an n-qubit quantum state takes 2 ⁿ -1 complex numbers. Presumably, the simulator will use a fixed integer or floating point width if the rounding error is ok.)

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