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Stronger no-cloning, no-signalling and conservation of quantum information

Indranil Chakrabarty·A. K. Pati·Satyabrata Adhikari
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Abstract

It is known that the stronger no-cloning theorem and the no-deleting theorem taken together provide the permanence property of quantum information. Also, it is known that the violation of the no-deletion theorem would imply signalling. Here, we show that the violation of the stronger no-cloning theorem could lead to signalling. Furthermore, we prove the stronger no-cloning theorem from the conservation of quantum information. These observations imply that the permanence property of quantum information is connected to the no-signalling and the conservation of quantum information.

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Indranil Chakrabarty, A. K. Pati, Satyabrata Adhikari. 2006-05-19. Stronger no-cloning, no-signalling and conservation of quantum information. https://arxiv.org/abs/quant-ph/0605173

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