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arXiv · 1304.7774

On universality of charge transport in AdS/CFT

Julian Sonner
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Abstract

We develop the holographic formulation of transport in strongly coupled two-layer systems. We identify a dc conductivity, sigma^dc, that is finite even in a translationally invariant setup, and universal for CFTs with a gravity dual. The thermoelectric conductivity and heat conductivity are fully determined by the electrical conductivity matrix, as a consequence of Ward identities. We use the memory-matrix approach for double-layer systems, together with Ward identities, to show that sigma^dc - extended to finite frequency - has no Drude peak and, similarly, that its universal value is unaffected if translation invariance is softly broken.

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Julian Sonner. 2013-05-17. On universality of charge transport in AdS/CFT. https://doi.org/10.1007/jhep07(2013)145

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