2015/06/30 by Subir Sachdev · 2 citations
Physics and Astronomy · #hep-th #cond-mat.str-el #gr-qc
paper · pdf · doi:10.1103/physrevx.5.041025
published as Phys. Rev. X 5, 041025 (2015) · 23 pages, 2 figures; (v2, v3, v4) added refs and clarifications
arxiv created 2015/08/12 · arxiv updated 2015/11/18
We examine models of fermions with infinite-range interactions which realize non-Fermi liquids with a continuously variable U(1) charge density Q, and a non-zero entropy density S at vanishing temperature. Real time correlators of operators carrying U(1) charge q at a low temperature T are characterized by a Q-dependent frequency ωS = (q T/ℏ) (∂ S/∂Q) which determines a spectral asymmetry. We show that the correlators match precisely with those of the AdS2 horizons of extremal charged black holes. On the black hole side, the matching employs S as the Bekenstein-Hawking entropy density, and the laws of black hole thermodynamics which relate (∂S/∂Q)/(2 π) to the electric field strength in AdS2. The fermion model entropy is computed using the microscopic degrees of freedom of a UV complete theory without supersymmetry.