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Moving quantum agents in a finite environment

Ilki Kim·Guenter Mahler
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Abstract

We investigate an all-quantum-mechanical spin network, in which a subset of spins, the $K$ ``moving agents'', are subject to local and pair unitary transformations controlled by their position with respect to a fixed ring of $M$ ``environmental''-spins. We demonstrate that a ``flow of coherence'' results between the various subsystems. Despite entanglement between the agents and between agent and environment, local (non-linear) invariants may persist, which then show up as fascinating patterns in each agent's Bloch-sphere. Such patterns disappear, though, if the agents are controlled by different rules. Geometric aspects thus help to understand the interplay between entanglement and decoherence.

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Ilki Kim, Guenter Mahler. 1999-02-06. Moving quantum agents in a finite environment. https://arxiv.org/abs/quant-ph/9902024

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