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arXiv · 2212.01214

Holographic two-point functions in medium

Chanyong Park·Se-Jin Kim·Jung Hun Lee
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Abstract

We study two-point correlation function in a medium composed of two kinds of matter, which is the dual of a three-dimensional generalized $p$-brane gas geometry. Following the holographic prescription, we calculate temporal and spatial two-point functions in the medium. In general, the screening effect of the medium makes two-point functions decrease more rapidly than the CFT's two-point function. In the extremal limit, however, we find that a temporal two-point function is still conformal. This indicates that a two-dimensional UV CFT flows into a one-dimensional quantum mechanics in the IR limit. This is consistent with the fact that the near horizon geometry in the extremal limit reduces to AdS$_2$. We also investigate holographic mutual information representing the correlation between two subsystems. We show that a critical distance in the IR region, where the mutual information vanishes, leads to a similar behavior to the correlation length of a two-point function.

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Chanyong Park, Se-Jin Kim, Jung Hun Lee. 2022-12-02. Holographic two-point functions in medium. https://arxiv.org/abs/2212.01214

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