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Quantum History cannot be Copied

Arun K. Pati
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Abstract

We show that unitarity does not allow cloning of any two points in a ray. This has implication for cloning of the geometric phase information in a quantum state. In particular, the quantum history which is encoded in the geometric phase during cyclic evolution of a quantum system cannot be copied. We also prove that the generalized geometric phase information cannot be copied by a unitary operation. We argue that our result also holds in the consistent history formulation of quantum mechanics.

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Arun K. Pati. 2005-07-26. Quantum History cannot be Copied. https://doi.org/10.1016/j.physleta.2005.08.041

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