QED2 as a testbed for interpolations between quenched and full QCD

Abstract

Lattice QED2 with the Wilson formulation of fermions is used as a convenient model system to study artifacts of the quenched approximation on a finite lattice. The quenched functional integral is shown to be ill-defined in this system as a consequence of the appearance of exactly real modes for physical values of the fermion mass. The location and frequency of such modes is studied as a function of lattice spacing, lattice volume, topological charge and improved action parameters. The efficacy of the recently proposed modified quenched approximation is examined, as well as a new approach to the interpolation from the quenched to full dynamical theory employing a truncated form of the fermion determinant.

Talk presented by A. Duncan at LATTICE97 (theoretical developments)

References in corpus (1)

• An Accelerated Conjugate Gradient Algorithm to Compute Low-Lying Eigenvalues --- a Study for the Dirac Operator in SU(2) Lattice QCD

Cited by in corpus (2)

• The chiral limit of the two-flavor lattice Schwinger model with Wilson fermions
• Tuning Actions and Observables in Lattice QCD