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Quantum deletion is possible via a partial randomization procedure

E. Elizalde
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Abstract

An alternative kind of deleting/erasing operation is introduced which differs from the commonly used {\it controlled-not} (C-not) conditional logical operation $-$to flip to a standard, `zero' value the (classical or quantum) state of the last copy in a chain, in a deletion process. It is completely reversible, in the classical case, possessing a most natural cloning operation counterpart. We call this deleting procedure R-deletion since, in a way, it can be viewed as a `randomization' of the standard C-not operator. It has the remarkable property of by-passing in a simple manner the `impossibility of deletion of a quantum state' principle, put forward by Pati and Braunstein recently \cite{pbn1}.

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E. Elizalde. 2000-10-24. Quantum deletion is possible via a partial randomization procedure. https://arxiv.org/abs/quant-ph/0007035

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