Confinement without a center: the exceptional gauge group G(2)
Michele Pepe


Abstract
I discuss theories with the exceptional gauge group G(2) as unusual framework to study confinement. Since the center of G(2) is trivial, a G(2) "quark" is screened by G(2) "gluons" and the string breaks already in the pure glue sector. Thus, similarly to QCD, confinement in G(2) Yang-Mills theory is not associated to a non-vanishing string tension.By the Higgs mechanism, the G(2) symmetry can be broken down to SU(3): a non-trivial center reemerges and this unusual form of confinement can be interpolated with the more familiar one of SU(3). I present numerical evidence for a finite temperature phase transition in G(2) Yang-Mills theory. Monte Carlo simulations with an Higgs field then allow to establish the connection between the finite temperature phase transition in G(2) and in SU(3) Yang-Mills theories.

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Elenco dei partecipanti al convegno di Bari.

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