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arXiv · 2402.10417

Entanglement Degradation in Causal Diamonds

H. E. Camblong·A. Chakraborty·P. Lopez-Duque·C. R. Ordóñez
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Abstract

Entanglement degradation appears to be a generic prediction in relativistic quantum information whenever horizons restrict access to a region of spacetime. This property has been previously explored in connection with the Unruh effect, where a bipartite entangled system composed of an inertial observer (Alice) and a uniformly accelerated observer (Rob) was studied, with entanglement degradation caused by the relative acceleration -- and with equivalent results for the case when Alice is freely falling into a black hole and Rob experiences a constant proper acceleration as a stationary near-horizon observer. In this work, we show that a similar degradation also occurs in the case of an entangled system composed of an inertial observer (Alice) and a "diamond observer" (Dave) with a finite lifetime. The condition of a finite lifetime is equivalent to the restriction of Dave's access within a causal diamond. Specifically, if the system starts in a maximally entangled state, prepared from Alice's perspective, entanglement degradation is enforced by the presence of the diamond's causal horizons.

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H. E. Camblong, A. Chakraborty, P. Lopez-Duque, C. R. Ordóñez. 2024-02-16. Entanglement Degradation in Causal Diamonds. https://doi.org/10.1103/physrevd.109.105003

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