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Higher representations on the lattice: perturbative studies

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 نشر من قبل Luigi Del Debbio
 تاريخ النشر 2008
  مجال البحث
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We present analytical results to guide numerical simulations with Wilson fermions in higher representations of the colour group. The ratio of $Lambda$ parameters, the additive renormalization of the fermion mass, and the renormalization of fermion bilinears are computed in perturbation theory, including cactus resummation. We recall the chiral Lagrangian for the different patterns of symmetry breaking that can take place with fermions in higher representations, and discuss the possibility of an Aoki phase as the fermion mass is reduced at finite lattice spacing.

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