Deconstructing holographic liquids

TL;DR

This work proposes a low-energy EFT for holographic liquids built from Goldstone bosons coupled to an infrared sector described by near-horizon holography. By treating the IR sector as emergent gravity and gauge fields, it unifies diffusion, hydrodynamics, and dissipative transport within a single framework, deriving the diffusion constant, the viscosity-to-entropy ratio $\eta/s=1/(4\pi)$, and holographic zero-sound dispersion from first principles. The approach provides a transparent interpretation of holographic transport phenomena and suggests deep connections between holography and condensed-matter models with emergent gauge/gravity structures. Overall, it offers a compact, physically transparent route to capture long-distance dynamics of strongly coupled quantum liquids using Goldstone dynamics plus IR holographic data, with potential broad applicability to zero-temperature and finite-density systems.

Abstract

We argue that there exist simple effective field theories describing the long-distance dynamics of holographic liquids. The degrees of freedom responsible for the transport of charge and energy-momentum are Goldstone modes. These modes are coupled to a strongly coupled infrared sector through emergent gauge and gravitational fields. The IR degrees of freedom are described holographically by the near-horizon part of the metric, while the Goldstone bosons are described by a field-theoretical Lagrangian. In the cases where the holographic dual involves a black hole, this picture allows for a direct connection between the holographic prescription where currents live on the boundary, and the membrane paradigm where currents live on the horizon. The zero-temperature sound mode in the D3-D7 system is also re-analyzed and re-interpreted within this formalism.

Figures (2)

• Figure 1: The moose diagram for holographic liquids.
• Figure 2: The division of space into two regions. The holographic IR modes live in the shaded region well below the cutoff.