Strange metal from holography
John McGreevy
MIT
Abstract
Techniques arising from
string theory can be used to study assemblies of strongly-interacting fermions.
Via these `holographic dualities', various strongly-coupled many body systems are
solved using an auxiliary theory of gravity. Simple holographic realizations of
finite density exhibit spectral functions with sharp Fermi surfaces, of a form
distinct from the Landau theory. Whether or not there exist long-lived quasiparticles depends on parameters of the gravity theory;
for some values, the system is a marginal Fermi liquid. The contribution to the
conductivity from these Fermi surfaces has an interesting
temperature dependence.