出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We report on our studies of topological properties of classical spherical center vortices with the low-lying eigenmodes of the Dirac operator in the fundamental and adjoint representations using both the overlap and asqtad fermion formulations. We confirm the discrepancy between the topological charge and the index of the Dirac operator, which was already found in a previous work of our group [Phys. Rev. D 77, 14515 (2008)] for overlap fermions, also for staggered fermions and adjoint representations. Furthermore, the index theorem of the adjoint fermions gives some evidence for fractional topological charge. During cooling the spherical center vortex on a 403×2 lattice we find an object with topological charge Q = 1/2 which we identify as a Dirac monopole without an antimonopole. For more details see [arXiv: hep-lat:1005.1015].
