Momentum dissipation and effective theories of coherent and incoherent transport Article Swipe
YOU?
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· 2015
· Open Access
·
· DOI: https://doi.org/10.1007/jhep01(2015)039
· OA: W2109998902
We study heat transport in two systems without momentum conservation: a\nhydrodynamic system, and a holographic system with spatially dependent,\nmassless scalar fields. When momentum dissipates slowly, there is a\nwell-defined, coherent collective excitation in the AC heat conductivity, and a\ncrossover between sound-like and diffusive transport at small and large\ndistance scales. When momentum dissipates quickly, there is no such excitation\nin the incoherent AC heat conductivity, and diffusion dominates at all distance\nscales. For a critical value of the momentum dissipation rate, we compute exact\nexpressions for the Green's functions of our holographic system due to an\nemergent gravitational self-duality, similar to electric/magnetic duality, and\nSL(2,R) symmetries. We extend the coherent/incoherent classification to\nexamples of charge transport in other holographic systems: probe brane theories\nand neutral theories with non-Maxwell actions.\n
