出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We study the influence of center vortices on the low-lying eigenmodes of the Dirac operator,
in both the overlap and asqtad formulations. For center-projected configurations, one finds that
the low-lying near-zero modes are present in the staggered (asqtad) formulation, but not in the
overlap and “chirally-improved" formulations. We argue that this is due to the absence of a fieldindependent
chiral symmetry in the latter formulations, when the Dirac operator is evaluated on
the very rough configurations generated by center projection. We also confirm and extend the
results of Kovalenko et al. [Phys. Lett. B 648, 383 (2007)], finding strong correlations between
center vortex locations, and the scalar density of low-lying Dirac eigenmodes on unprojected lattices,
in both asqtad and overlap formulations. It is found that the low-lying eigenmodes have their
largest concentrations in point-like regions, rather than on submanifolds of higher dimensionality.
