Confinement in G(2) gauge theories using the thick center vortex model and domain structures

Abstract

The thick center vortex model, with the idea of using domain structures, is used to calculate the potentials between two G(2) heavy sources in the fundamental, the adjoint, and the 27-dimensional representations. The potentials are screened at large distances. This behavior is expected from the thick center vortex model since G(2) has only a trivial center element which makes no contribution to the average Wilson loop at the large distance regime. A linear potential is obtained at intermediate distances for all representations. This behavior can be explained by the thickness of the vortices (domains) and by defining a flux for the trivial center element of G(2). The role of the SU(3) subgroup of G(2) in the linear regime is also discussed. The string tensions are in rough agreement with the Casimir operators of the corresponding representations.