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arXiv · 1211.1214

Application of Domain Decomposition to the Evaluation of Fermion Determinant Ratios

Jacob Finkenrath·Francesco Knechtli·Björn Leder
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Abstract

We analyze the fluctuations in the case of mass reweighting for N_f=2 Wilson fermions. We use a domain decomposition factorization of the fermion determinant. Ratios of determinants are estimated stochastically. We study the stochastic and the ensemble fluctuations as a function of the volume V and the mass shift Delta m. With our result it is possible to estimate the cost and the effectiveness of mass reweighting. In addition we introduce a stochastic estimation for the one flavor case without using the square root.

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Jacob Finkenrath, Francesco Knechtli, Björn Leder. 2013-09-30. Application of Domain Decomposition to the Evaluation of Fermion Determinant Ratios. https://arxiv.org/abs/1211.1214

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