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arXiv · 2008.09638

Holographic subdiffusion

Koushik Ganesan·Andrew Lucas
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Abstract

We initiate a study of finite temperature transport in gapless and strongly coupled quantum theories with charge and dipole conservation using gauge-gravity duality. In a model with non-dynamical gravity, the bulk fields of our model include a suitable mixed-rank tensor which encodes the boundary multipole symmetry. We describe how such a theory can arise at low energies in a theory with a covariant bulk action. Studying response functions at zero density, we find that charge relaxes via a fourth-order subdiffusion equation, consistent with a recently-developed field-theoretic framework.

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Koushik Ganesan, Andrew Lucas. 2020-08-21. Holographic subdiffusion. https://doi.org/10.1007/jhep12(2020)149

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