title: Chaos in fermionic many-body systems and the metal-insulator transition.
abstract: We show that finite Fermi systems governed by a mean field and a few-body interaction generically possess spectral fluctuations of the Wigner-Dyson type and are, thus, chaotic. Our argument is based on an analogy to the metal-insulator transition. We construct a sparse random-matrix scaffolding ensemble (ScE) that mimics this transition. Our claim then follows from the fact that the generic random-matrix ensemble modeling a fermionic interacting many-body system is much less sparse than ScE.
authors.affiliation: Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA.
authors.forename: T
authors.initials: T
authors.lastname: Papenbrock
authors.forename: Z
authors.initials: Z
authors.lastname: Pluhař
authors.forename: J
authors.initials: J
authors.lastname: Tithof
authors.forename: H A
authors.initials: HA
authors.lastname: Weidenmüller