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Continuous variable entanglement sharing in non-inertial frames

Gerardo Adesso·Ivette Fuentes-Schuller·Marie Ericsson
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Abstract

We study the distribution of entanglement between modes of a free scalar field from the perspective of observers in uniform acceleration. We consider a two-mode squeezed state of the field from an inertial perspective, and analytically study the degradation of entanglement due to the Unruh effect, in the cases of either one or both observers undergoing uniform acceleration. We find that for two observers undergoing finite acceleration, the entanglement vanishes between the lowest frequency modes. The loss of entanglement is precisely explained as a redistribution of the inertial entanglement into multipartite quantum correlations among accessible and unaccessible modes from a non-inertial perspective. We show that classical correlations are also lost from the perspective of two accelerated observers but conserved if one of the observers remains inertial.

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Gerardo Adesso, Ivette Fuentes-Schuller, Marie Ericsson. 2007-10-26. Continuous variable entanglement sharing in non-inertial frames. https://doi.org/10.1103/physreva.76.062112

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