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arXiv · 2305.04952

Geometric Quantum Discord Signals Non-Factorization

Souvik Banerjee·Pablo Basteiro·Rathindra Nath Das·Moritz Dorband
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Abstract

We propose the information-theoretic quantity of geometric quantum discord (GQD) as an indicator of the factorization properties of a given quantum system. In particular, we show how non-vanishing discord implies that the corresponding partition function does not factorize, both for generic pure states and the thermofield double state as a state with a known geometric dual in light of the AdS/CFT correspondence. Via this analysis, we give a novel interpretation to the thermomixed double state as the best purely classical approximation of the Einstein-Rosen bridge. We connect the non-vanishing of GQD with the existence of wormhole microstates.

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Souvik Banerjee, Pablo Basteiro, Rathindra Nath Das, Moritz Dorband. 2023-05-08. Geometric Quantum Discord Signals Non-Factorization. https://doi.org/10.1007/jhep08(2023)104

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