出版社:SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要:The ghost propagator and the Coulomb potential are evaluated in Coulomb gauge on the lattice,
using an improved gauge fixing scheme which includes the residual symmetry. This setting has
been shown to be essential in order to explain the scaling violations in the instantaneous gluon
propagator. We find that both the ghost propagator and the Coulomb potential are insensitive
to the Gribov problem or the details of the residual gauge fixing, even if the Coulomb potential
is evaluated from the A0–propagator instead of the Coulomb kernel. In particular, no signs of
scaling violations could be found in either quantity, at least to well below the numerical accuracy
where these violations were visible for the gluon propagator. The Coulomb potential from the
A0-propagator is shown to be in qualitative agreement with the (formally equivalent) expression
evaluated from the Coulomb kernel.