FM 01-10; mp_arc 00-??? nlin/CD 0007???
Authors: G. Benfatto, V. Mastropietro
Title: On the density-density critical indices in interacting Fermi
Abstract: The behaviour of correlation functions of $d=1$ interacting
fermionic systems is determined by a small number of critical
indices. We prove that one of them is exactly zero. As a consequence,
the behavior of the Fourier transform of the density-density
correlation at zero momentum is qualitatively unaffected by the
interaction, contrary to what happens at $\pm 2 \tilde p_F$, if
$\tilde p_F$ is the Fermi momentum. The result is obtained by
implementing Ward identities in a Renormalization Group approach.
Key words: Critical indices, Ward identities, spin chains.
G.Benfatto, V. Mastropietro
Universita' di Roma 2, Dip. Matematica
Via Fontanile di Carcaricola
00133 Roma, Italia