Quantum register

A quantum register is a system comprising multiple qubits and is the quantum analog of the classical processor register.

An ${\displaystyle n}$ size quantum register is a quantum system comprising ${\displaystyle n}$ qubits.

The Hilbert space, ${\displaystyle {\mathcal {H}}}$, in which the data stored in a quantum register is${\displaystyle {\mathcal {H}}={\mathcal {H_{n-1}}}\otimes {\mathcal {H_{n-2}}}\otimes \ldots \otimes {\mathcal {H_{0}}}}$.

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