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arXiv · 2112.02924

Complex Langevin boundary terms in lattice models

Michael W. Hansen·Erhard Seiler·Dénes Sexty·Ion-Olimipu Stamatescu
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Abstract

In complex Langevin simulations, the insufficient decay of the probability density near infinity leads to boundary terms that spoil the formal argument for correctness. We present a formulation of this term that is cheaply measurable in lattice models, and in principle allows also the direct estimation of the systematic error of the CL method. Results for a toy model, 3d XY model and HDQCD are presented.

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Michael W. Hansen, Erhard Seiler, Dénes Sexty, Ion-Olimipu Stamatescu. 2021-12-06. Complex Langevin boundary terms in lattice models. https://arxiv.org/abs/2112.02924

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