How good is the quenched approximation of QCD?

Abstract

The quenched approximation for QCD is, at present and in the foreseeable future, unavoidable in lattice calculations with realistic choices of the lattice spacing, volume and quark masses. In this talk, I review an analytic study of the effects of quenching based on chiral perturbation theory. Quenched chiral perturbation theory leads to quantitative insight on the difference between quenched and unquenched QCD, and reveals clearly some of the diseases which are expected to plague quenched QCD. Uses jnl.tex and epsf.tex for figure 3. Figures 1 and 2 not included, sorry. Available as hardcopy on request.

22 pages, Wash. U. HEP/94-62 (Forgotten set of macros now included, sorry.)

References in corpus (7)

• Chiral Perturbation Theory for the Quenched Approximation of QCD
• Quenched Chiral Logarithms
• Partially Quenched Gauge Theories and a Application to Staggered Fermions
• Critical Analysis of Baryon Masses and Sigma-Terms in Heavy Baryon Chiral Perturbation Theory
• Hadron Mass Predictions of the Valence Approximation to Lattice QCD
• $I=2$ pion scattering amplitude with Wilson fermions
• The Quenched Approximation in Health and in Sickness

Cited by in corpus (2)

• Quenched Approximation Artifacts: A study in 2-dimensional QED
• Lattice Gauge Fixing and the Violation of Spectral Positivity