The Hubbard model at half-filling, part III: the lower bound on the self-energy
arXiv:cond-mat/0412401 · doi:10.1007/s00023-005-0214-z
Abstract
We complete the proof that the two-dimensional Hubbard model at half-filling is not a Fermi liquid in the mathematically precise sense of Salmhofer, by establishing a lower bound on a second derivative in momentum of the first non-trivial self-energy graph.
31 pages, 4 figures