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arXiv · 1801.07823

Multigrid for Staggered Lattice Fermions

Richard C. Brower·M. A. Clark·Alexei Strelchenko·Evan Weinberg
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Abstract

Critical slowing down in Krylov methods for the Dirac operator presents a major obstacle to further advances in lattice field theory as it approaches the continuum solution. Here we formulate a multi-grid algorithm for the Kogut-Susskind (or staggered) fermion discretization which has proven difficult relative to Wilson multigrid due to its first-order anti-Hermitian structure. The solution is to introduce a novel spectral transformation by the K\"ahler-Dirac spin structure prior to the Galerkin projection. We present numerical results for the two-dimensional, two-flavor Schwinger model, however, the general formalism is agnostic to dimension and is directly applicable to four-dimensional lattice QCD.

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Richard C. Brower, M. A. Clark, Alexei Strelchenko, Evan Weinberg. 2018-01-24. Multigrid for Staggered Lattice Fermions. https://doi.org/10.1103/physrevd.97.114513

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