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Speeding up finite step-size updating of full QCD on the lattice

M. Hasenbusch
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Abstract

We propose various improvements of finite step-size updating for full QCD on the lattice that might turn finite step-size updating into a viable alternative to the hybrid Monte Carlo algorithm. These improvements are noise reduction of the noisy estimator of the fermion determinant, unbiased inclusion of the hopping parameter expansion and a multi-level Metropolis scheme. First numerical tests are performed for the 2 dimensional Schwinger model with two flavours of Wilson fermions and for QCD two flavours of Wilson fermions and Schr"odinger functional boundary conditions.

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M. Hasenbusch. 1998-07-17. Speeding up finite step-size updating of full QCD on the lattice. https://doi.org/10.1103/physrevd.59.054505

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