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arXiv · 1503.02695

Entanglement over the rainbow

Giovanni Ramírez·Javier Rodríguez-Laguna·Germán Sierra
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Abstract

In one dimension the area law for the entanglement entropy is violated maximally by the ground state of a strong inhomogeneous spin chain, the so called concentric singlet phase (CSP), that looks like a rainbow connecting the two halves of the chain. In this paper we show that, in the weak inhomogeneity limit, the rainbow state is a thermofield double of a conformal field theory with a temperature proportional to the inhomogeneity parameter. This result suggests some relation of the CSP with black holes. Finally, we propose an extension of the model to higher dimensions.

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Giovanni Ramírez, Javier Rodríguez-Laguna, Germán Sierra. 2015-03-09. Entanglement over the rainbow. https://doi.org/10.1088/1742-5468/2015/06/p06002

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