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arXiv · 2011.12949

Origin and Limit of the Recovery of Damaged Information by Time Reversal

Xiangyu Cao·Thomas Scaffidi
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Abstract

Recently it was found that scrambled information can be partially recovered by a time-reversed evolution, even after being damaged by an intruder. We reconsider the origin of the information recovery, and argue that the presence of classical chaos does not preclude it and only leads to a quantitative reduction of the recovery ratio. We also show how decoherence (i.e. entanglement with the intruder) limits the recovery, by proving an upper bound on the recovery ratio in terms of the entangling power of the intruder's action.

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Xiangyu Cao, Thomas Scaffidi. 2020-11-25. Origin and Limit of the Recovery of Damaged Information by Time Reversal. https://doi.org/10.1103/physreva.103.l020401

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