Holography without translational symmetry

David Vegh

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arXiv · 1301.0537

Holography without translational symmetry

David Vegh

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Abstract

We propose massive gravity as a holographic framework for describing a class of strongly interacting quantum field theories with broken translational symmetry. Bulk gravitons are assumed to have a Lorentz-breaking mass term as a substitute for spatial inhomogeneities. This breaks momentum-conservation in the boundary field theory. At finite chemical potential, the gravity duals are charged black holes in asymptotically anti-de Sitter spacetime. The conductivity in these systems generally exhibits a Drude peak that approaches a delta function in the massless gravity limit. Furthermore, the optical conductivity shows an emergent scaling law: $|σ(ω)| \approx {A \over ω^α} + B$. This result is consistent with that found earlier by Horowitz, Santos, and Tong who introduced an explicit inhomogeneous lattice into the system.

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David Vegh. 2013-01-15. Holography without translational symmetry. https://arxiv.org/abs/1301.0537

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