Strongly correlated quantum fluids: ultracold quantum gases, quantum chromodynamic plasmas and holographic duality

Abstract

Strongly correlated quantum fluids are phases of matter that are\nintrinsically quantum mechanical, and that do not have a simple description in\nterms of weakly interacting quasi-particles. Two systems that have recently\nattracted a great deal of interest are the quark-gluon plasma, a plasma of\nstrongly interacting quarks and gluons produced in relativistic heavy ion\ncollisions, and ultracold atomic Fermi gases, very dilute clouds of atomic\ngases confined in optical or magnetic traps. These systems differ by more than\n20 orders of magnitude in temperature, but they were shown to exhibit very\nsimilar hydrodynamic flow. In particular, both fluids exhibit a robustly low\nshear viscosity to entropy density ratio which is characteristic of quantum\nfluids described by holographic duality, a mapping from strongly correlated\nquantum field theories to weakly curved higher dimensional classical gravity.\nThis review explores the connection between these fields, and it also serves as\nan introduction to the Focus Issue of New Journal of Physics on Strongly\nCorrelated Quantum Fluids: from Ultracold Quantum Gases to QCD Plasmas. The\npresentation is made accessible to the general physics reader and includes\ndiscussions of the latest research developments in all three areas.\n