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arXiv · 2304.10438

Gauge-equivariant pooling layers for preconditioners in lattice QCD

Christoph Lehner·Tilo Wettig
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Abstract

We demonstrate that gauge-equivariant pooling and unpooling layers can perform as well as traditional restriction and prolongation layers in multigrid preconditioner models for lattice QCD. These layers introduce a gauge degree of freedom on the coarse grid, allowing for the use of explicitly gauge-equivariant layers on the coarse grid. We investigate the construction of coarse-grid gauge fields and study their efficiency in the preconditioner model. We show that a combined multigrid neural network using a Galerkin construction for the coarse-grid gauge field eliminates critical slowing down.

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Christoph Lehner, Tilo Wettig. 2023-04-20. Gauge-equivariant pooling layers for preconditioners in lattice QCD. https://arxiv.org/abs/2304.10438

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