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Topological susceptibility in full QCD with Ginsparg-Wilson fermions

L. Giusti·G. C. Rossi·M. Testa
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Abstract

We show that, if the formula for the topological charge density operator suggested by fermions obeying the Ginsparg-Wilson relation is employed, it is possible to give a precise and unambiguous definition of the topological susceptibility in full QCD, chi_tL, for finite quark masses on the lattice. The lattice expression of chi_tL looks like the formal continuum one, in the sense that no power divergent subtractions are needed for its proper definition. As a consequence, the small mass behaviour of chi_tL leads directly to a multiplicative renormalizable definition of the chiral condensate that does not require any power divergent subtraction.

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L. Giusti, G. C. Rossi, M. Testa. 2004-02-23. Topological susceptibility in full QCD with Ginsparg-Wilson fermions. https://doi.org/10.1016/j.physletb.2004.03.010

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