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arXiv · 1111.5303

Conductivity and quasinormal modes in holographic theories

M. A. Stephanov·Y. Yin
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Abstract

We show that in field theories with a holographic dual the retarded Green's function of a conserved current can be represented as a convergent sum over the quasinormal modes. We find that the zero-frequency conductivity is related to the sum over quasinormal modes and their high-frequency asymptotics via a sum rule. We derive the asymptotics of the quasinormal mode frequencies and their residues using the phase-integral (WKB) approach and provide analytic insight into the existing numerical observations concerning the asymptotic behavior of the spectral densities.

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M. A. Stephanov, Y. Yin. 2011-11-22. Conductivity and quasinormal modes in holographic theories. https://doi.org/10.1007/jhep02(2012)017

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