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arXiv · hep-lat/0610098

Automatic O$(a)$ improvement for twisted-mass QCD

Sinya Aoki·Oliver Bär
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Abstract

We present a condition for automatic O$(a)$ improvement in twisted mass lattice QCD, using symmetries of the Symanzik effective theory. If the continuum part of the Symanzik effective theory is invariant under a particular transformation, named $T_1$ in this report, scaling violations of all quantities invariant under $T_1$ transformation are even in the lattice spacing $a$. On the other hand, quantities non-invariant under $T_1$ vanish in the continuum limit with odd powers in $a$. We prove this statement even for the massive case without using the equation of motion. We also consider a few different criteria for the $T_1$ invariant condition in lattice theories and discuss ambiguities of the lattice condition for O$(a)$ improvement.

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Sinya Aoki, Oliver Bär. 2006-10-18. Automatic O$(a)$ improvement for twisted-mass QCD. https://arxiv.org/abs/hep-lat/0610098

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