SciPost Phys. Core 2, 011 (2020) ·
published 29 June 2020
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· pdf
We assess numerical stabilization methods employed in fermion many-body
quantum Monte Carlo simulations. In particular, we empirically compare various
matrix decomposition and inversion schemes to gain control over numerical
instabilities arising in the computation of equal-time and time-displaced
Green's functions within the determinant quantum Monte Carlo (DQMC) framework.
Based on this comparison, we identify a procedure based on pivoted QR
decompositions which is both efficient and accurate to machine precision. The
Julia programming language is used for the assessment and implementations of
all discussed algorithms are provided in the open-source software library
StableDQMC.jl [http://github.com/crstnbr/StableDQMC.jl].
Mr Bauer: "We thank the referee for his/h..."
in Report on Fast and stable determinant quantum Monte Carlo